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Experimental and analytical thermal study of PTFE composite sliding against high carbon steel as a function of the surface roughness, sliding velocity and applied load
PublicationThis study investigates the contact temperatures caused by frictional heating of sliding parallel pairs. In this case the materials studied are a PTFE composite in contact with a high carbon steel plate. These materials are commonly used for industrial applications, in particular as the main contacting components within a scroll expander system. The expected contact temperature values are important to be quantified in order to...
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Multi-instrument analysis of L-band amplitude scintillation observed over the Eastern Arabian Peninsula
PublicationThe study of scintillation-causing ionospheric irregularities is important to mitigate their effects on satellite communications. It is also important due to the spatial and temporal variability of these irregularities, given that their characteristics differ from one region to another. This study investigates the spatial and temporal characteristics of L1 amplitude scintillation-causing ionospheric irregularities over the Eastern...
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Development of fragility curves in adjacent steel moment-resisting frames considering pounding effects through improved wavelet-based refined damage-sensitive feature
PublicationFragility curves present useful information related to earthquake-induced probability assessment of steel moment-resisting frames (MRFs) and determine the probability of the damage exceedance at different floor levels of MRFs. The review of the literature shows that most of the previous studies dealing with the fragility curves were based on conventional measures, such as spectral acceleration at the first mode period, peak...
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Wavelet transform analysis to assess oscillations in pial artery pulsation at the human cardiac frequency
PublicationPial artery adjustments to changes in blood pressure (BP)may last only seconds in humans. Using a novelmethod called near-infrared transillumination backscattering sounding (NIR-T/BSS) that allows for the non-invasive measurement of pial artery pulsation (cc-TQ) in humans, we aimed to assess the relationship between spontaneous oscillations in BP and cc-TQ at frequencies between 0.5 Hz and 5 Hz. We hypothesized that analysis of...
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Weakly nonlinear dynamics of short acoustic waves in exponentially stratified gas
PublicationRozpatruje się dynamika krótkich (w porównywaniu z charakterystyczną skalą zmiany gęstości gazu atmosferycznego) fal akustycznych. Wyprowadzone nowe równanie ewolucyjne, które uwzględnia dyspersję i nieliniowy charakter propagacji tych fal. Porównuje sie liniowa i nieliniowa dynamika. Ilustracje propagacji, numeryczne wyliczione na podstawie nowych wzorów, są przedstawione. Indexed and abstracted (from vol. 32(1) 2007) in Science...
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Dynamics of Field Line Mappings in Magnetic Flux Tubes
PublicationWe study the topological constraints on the dynamics of magnetic field lines in flux tubes. Our approach is based on the application of the topological invariant: fixed point index. We consider periodic flux tubes and find various restrictions on the field lines that come from the sequence of fixed point indices of iterations. We also analyze the case of a tube with a cylindrical obstacle, deducing some special dynamical properties...
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The main developments of the CSR initiatives in Poland
PublicationThis short paper outlines the most important documents and initiatives that have appeared in the subject throughout the years within the international institutions, such as United Nations or European Union. It also discusses the ways in which the international CSR initiatives are being incorporated into Polish legislative and organizational system, by providing an outline of the biggest and most active organizations and foundations...
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Optical fiber aptasensor for label-free bacteria detection in small volumes
PublicationHighly sensitive devices for fast bacteria detection are sought to be developed with the task of quantifying the worldwide problem of pathogenic bacteria and thus helping to take control over spreading bacterial infections. This work concerns a sensing solution based on microcavity in-line Mach-Zehnder interferometer (μIMZI) induced in an optical fiber. Such a device exhibits ultrahigh sensitivity to refractive index changes...
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A total scoring system and software for complex modified GAPI (ComplexMoGAPI) application in the assessment of method greenness
PublicationEvaluating analytical methods with innovative metrics is essential to ensure the effectiveness of analytical procedures. Various approaches have been proposed to assess the performance of an analytical method and its environmental consequences, as sustainable environment and green chemistry ideology are of high importance nowadays. Considering greenness evaluation of developed analytical procedures, Green Analytical Procedure Index...
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Polish Adaptation of the Pregnancy-Related Anxiety Questionnaire—Revised 2 for All Pregnant Women
PublicationPregnancy-related anxiety (PrA) is a specific type of anxiety characteristic of the perinatal period. PrA can affect pregnancy and birth. However, no validated tool exists to measure PrA in Polish obstetric practice. The aim of this study was to translate the Pregnancy-Related Anxiety Questionnaire—Revised 2 (PRAQ-R2) into Polish and to evaluate its reliability and factorial and construct validity. This study was conducted in Poland...
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Overview of Metamaterials-Integrated Antennas for Beam Manipulation Applications: The Two Decades of Progress
PublicationMetamaterials (MMs) are synthetic composite structures with superior properties not found in naturally occurring materials. MMs have gained massive attention over the last two decades because of their extraordinary properties, such as negative permittivity and permeability. These materials enable many applications in communication subsystems, especially in the field of antenna design, to enhance gain, bandwidth, and efficiency,...
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Size-exclusion chromatography for the determination of the boiling point distribution of high-boiling petroleum fractions
PublicationThe paper describes a new procedure for the determination of boiling point distribution of high-boiling petroleum fractions using size exclusion chromatography with refractive index detector. Thus far, the determination of boiling range distribution by chromatography has been accomplished using simulated distillation with gas chromatography with the flame ionization detection. This study revealed that in spite of substantial differences...
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Wpływ termoplastycznych kompozycji napełnianych miałem gumowym na wybrane właściwości asfaltu drogowego
PublicationDynamiczny rozwój transportu samochodowego zmusza do wykonywania nawierzchni drogowych z materiałów o wysokiej wytrzymałości oraz odporności na odkształcenia trwałe, co znacznie wydłuża żywotność nawierzchni. Polskie przedsiębiorstwo BISEK Sp. z o.o. z Wrocławia we współpracy z Politechniką Wrocławską, jako pierwsze wykorzystało miał gumowy do modyfikacji asfaltów metodą mokrą. W chwili obecnej firma Lotos Asfalt Sp. z o.o. wprowadziła...
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OCENA EFEKTYWNOŚCI DZIAŁALNOŚCI BADAWCZO-ROZWOJOWEJ W KRAJACH OECD
PublicationDziałalność badawczo-rozwojowa jest istotną częścią polityki innowacyjnej. Ocenę tej działalności w krajach OECD przeprowadzono wykorzystując metodę DEA. Uwzględniono nakłady: poziom wykształcenia, współpracę nauki z biznesem i poziom wykorzystywania wiedzy w firmach oraz rezultaty: liczba publikacji, patentów i doktoratów oraz eksport sektorów wysokich technologii i indeks Hirsha. Zwrócono uwagę na problem zerowych wag oraz przesunięcia...
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TEST FOR ASSESSING THE ENERGY EFFICIENCY OF VEHICLES WITH INTERNAL COMBUSTION ENGINES
PublicationThe most popular method for assessing the energy efficiency of vehicles is to compare the fuel consumption achieved in the conditions of selected approval test. Operating conditions are defined using the speed profiles, usually for only two categories: urban and extra-urban driving. Assessing the energy efficiency of vehicles should be performed using a more detailed classification of conditions. Presented results of comparison...
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Programy komputerowe a style uczenia się
PublicationW artykule podjęto tematykę uczenia się obsługi programów komputerowych w kontekście różnych stylów uczenia się użytkowników. Badania są przeprowadzone na styku użytkownik - program komputerowy; z jednej strony występuje człowiek z jego własnościami psychologicznymi, z drugiej zaś program komputerowy ze cechami wynikającymi z jego budowy i działania. Analizy empiryczne przeprowadzono na przykładzie nauki obsługi programu graficznego...
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The Efficiency of Polish Stock Market: Ordinal Patterns Approach
PublicationZunino et al. analyzed the problem of discrimination of developed and emergent markets by the use of ordinal patterns methods: number of forbidden patterns and ordinal pattern probability distribution as a basis for entropy and statistical measure of complexity. In this paper we apply the same methodology for the analysis of Polish stock market (index WIG). The results indicate that Polish market belongs neither to developed, nor...
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Design of septic tanks placed on cohesive soils
PublicationThe paper presents a short review of literature with regard to design and erection of the reinforced concrete and concrete tanks. The authors investigated the underground septic tank with of 10 m3 capacity placed on cohesive soils. The authors compared the values of internal forces for soils in drained and undrained conditions with different geotechnical parameters: loamy sand of liquidity index IL = 0.1 and IL = 0.7 and clay with...
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Effect of the ex situ physical and in situ chemical modification of bacterial nanocellulose on mechanical properties in the context of its potential applications in heart valve design
PublicationBacterial nanocellulose (BNC) is a promising material for heart valve prostheses. However, its low strength properties limit its applicability in cardiovascular surgery. To overcome these limitations, the mechanical properties of BNC can be improved through modifications. The aim of the research was to investigate the extent to which the mechanical properties of BNC can be altered by modifying its structure during its production...
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Real-time isothermal DNA amplification monitoring in picoliter volumes using an optical fiber sensor
PublicationRolling circle amplification (RCA) of DNA can be considered as a great alternative to the gold standard polymerase chain reaction (PCR), especially during this pandemic period, where rapid, sensitive, and reliable test results for hundreds of thousands of samples are required daily. This work presents the first research to date on direct, real-time and label-free isothermal DNA amplification monitoring using a microcavity in-line...
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Probabilistic analysis of settlements under a pile foundation of a road bridge pylon
PublicationThe paper addresses the reliability change of a road bridge pile foundation due to the unpredictable increase of settlements in time. The analysis is based on the Rędziński Bridge in Wrocław, Poland, its design assumptions, and monitoring results. The bridge foundation rests on a multi-layered subsoil assumed random. The Finite Element model of the subgrade is generated in ZSoil® software. To simplify the probabilistic approach,...
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Rheology of potato starch chemically modified with microwave-assisted reactions
PublicationNative potato starch was sulfated, selenated, borated, silicated and zincatated by means of microwave-assisted reactions with varying doses of relevant reagents. Resulting products were characterized involving rheological behavior of pastes, their weight-average molecular weight (Mw), and radius of gyration (Rg). Most of the pastes showed shear-thinning behavior, with the flow behavior index (n) below unity. The pastes of starch...
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Modeling of Cardiac Component of Subarachnoid Space Changes in Apnoea Resulting as a Function of Blood Pressure and Blood Flow Parameters - Two Mechanizm of Regulation
PublicationExperiments were performed in a group of 19 healthy, non-smoking volunteers. The experiment consisted of three apnoeas, sequentially: 30 s apnoea, 60 s apnoea and maximal, that could be done, apnoea. The breath-hold was separated for 5 minutes rest. The following parameters were measured and obtained for further analysis: blood parameters, artery diameter of the internal carotid artery, end-tidal CO2 in expired air, the cardiac...
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Fighting Administrative Corruption with Digital Government in Sub-Saharan Africa
PublicationAdministrative corruption is a pervasive problem and a major threat to economic and social development around the world, especially in Sub-Saharan Africa which lags behind other regions in various development indicators and is seen as one of the most corrupt regions globally. This paper examines a hypothesis that digital government – the use of digital technology to transform public administration organizations and their relationships...
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Indykatory dla modelu społeczeństwa informacyjnego.
PublicationW dobie postępującej informatyzacji, w czasach nazywanych często trzecią rewolucją technologiczną, synonimem ich jest społeczeństwo informacyjne IS (Information Society). Najpopularniejszy obecnie sposób, służący do szeregowania społeczeństw według ich stopnia rozwoju, jest oparty na HDI (Human Development Index). HDI jest wyliczany jako kombinacja trzech wyznaczników: longevity, knowledge, and a decent standard of living. Postanowiono,...
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Characterization of Corrosion-Induced Fracture in Reinforced Concrete Beams Using Electrical Potential, Ultrasound and Low-Frequency Vibration
PublicationThe paper deals with the non-destructive experimental testing of the reinforced concrete beams under progressive corrosion. A series of experiments using electrical potential, ultrasound and low-frequency vibrations techniques are reported. Electrical potential and natural frequencies were used to characterise and monitor the corrosion process at its initial state. The P-wave velocity measurements were proved to be effective in...
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PROCESSING, MECHANICAL AND THERMAL PROPERTIES OF RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublicationThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for the potential methods of their utilization. Nevertheless, for the efficient application of recycled materials it is crucial to analyze their performance. Therefore, in presented paper we investigated the processing (melt flow index),...
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Ab-initio study of electrical and optical properties of allylamine
PublicationThe Density functional theory is one of most promising methodology in fast and accurate calculations of electrical and optical properties from the atomic basis. In this paper, we calculate electrical and optical properties of allylamine (2-propen 1- amine) in terms of accuracy and speed of calculations obtained by selection of DFT-1/2 method with ultrasoft Vanderbilt pseudopotentials. Comparison of density of states between...
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Influence of statistical errors on damage detection based on structuralflexibility and mode shape curvature
PublicationDamage detection procedures based on measured natural frequencies and building structure mode shapes are discussed in this paper. Modal curvature and structural flexibility approaches are tested. Attention is paid to the modal identification errors that influence damage detection. This problem is studied using a computer simulation of a simple supported beam. For practical cases, the peak picking methodand its statistical errors...
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The Impact of Concentration on Secors' Output Level in the European Union (1997-2005)
PublicationThis paper examines the impact of concentration on growthof selected 43 sectors within ten European countries over the period of time 1997-2005. We apply system GMM estimator to the extendedversion of production function, including as explanatory variablesindustry specific measures of concentration. We found the relationbetween output and concentration measured by the Herfindahl-Hirschman Index (HHI) to be non-monotonic having...
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Vibroflotation Control of Sandy Soils using DMT and CPTU
PublicationVibroflotation is a typical improvement method for the cohesionless deposits of high thickness. The compaction method was applied to densify sandy deposits in Gdynia Port. Compaction control was verified with CPTU and DMT tests. Some examples of interpretation of soundings in pre-treated and compacted sands are shown. The classification diagrams are given for pre-treated and compacted sand. The stress history of the deposits is...
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Optical properties of boron-doped nanocrystalline diamond films studied by spectroscopic ellipsometry
PublicationThe optical properties of boron-doped nanocrystalline diamond films, coated using Microwave Plasma Enhanced Chemical Vapour Deposition (μPE CVD) system, were analyzed by spectroscopic ellipsometry. Diamond films were deposited on silicon substrates. The ellipsometry data (refractive index (n(λ)), extinction coefficient (k(λ)) were modeled using dedicated software. Evolution of the optical structure with boron doping was observed...
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Synthesis and antiproliferative activity of new mycophenolic acid conjugates with adenosine derivatives
PublicationNew conjugates of mycophenolic acid (MPA) and adenosine derivatives were synthesized and assessed as potential immunosuppressants on Jurkat cell line and peripheral blood mononuclear cells (PBMC) from healthy donors. As compared to MPA, all compounds were found to be more active against Jurkat cell line. The antiproliferative activities were compared with MPA and adenosine, in both 2′,3′-O-isopropylidene protected and free hydroxyl...
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Ab-initio study of electrical and optical properties of allylamine
PublicationThe Density functional theory is one of most promising methodology in fast and accurate calculations of electrical and optical properties from the atomic basis. In this paper, we calculate electrical and optical properties of allylamine (2-propen 1- amine) in terms of accuracy and speed of calculations obtained by selection of DFT-1/2 method with ultrasoft Vanderbilt pseudopotentials. Comparison of density of states between molecule...
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Synergistic Effects of Propolis Combined with 2-Phenoxyethanol and Antipyretics on the Growth of Staphylococcus aureus
PublicationThe present investigation aimed to assess the combinational effect of commonly usedantipyretics and antiseptics with ethanolic extracts of propolis (EEPs) on the growth inhibition ofStaphylococcus aureus. The broth microdilution checkerboard assay revealed synergistic interactionsbetween all investigated antipyretics, namely acetylsalicylic acid, ibuprofen, and acetaminophen,with EEPs samples. The values of the fractional inhibitory...
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How Does International Competitiveness Affect Economic Development? A Two-Phase Hypothesis
PublicationThis paper analyses the impact of international competitiveness on economic development, based on the World Economic Forum Global Competitiveness Index (GCI) and GDP/capita of 125 countries during the period 2007-2010. The results reveal two phases of the evolution of competitiveness. When GCI < 4.5 (on 1-7 scale), any improvement of a country’s competitiveness affects current development more than future development. When...
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Time-frequency analysis of acoustic signals using concentrated spectrogram
PublicationThe paper presents improved method of time-frequency (TF) analysis of discrete-time signals. The method involves signal's local group delay (LGD) and channelized instantaneous frequency (CIF) to purposely redistribute all Short-time Fourier transform (STFT) lines. Additionally, the energy concentration index (ECI) and some histogram-like statistics are used to evaluate readability of estimated TF distributions of the energy. Recorded...
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Subsoil degradation effect in reliability analysis of the jack-up platform structure
PublicationStructural reliability analysis is considered, by FORM and SORM applied to a certain idealized soil-platform structure interaction problem due to cyclic water wave and wind loads. Wave and wind loads are random variables, whereas dead load is deterministic. Load parameters are typical for storm conditions in the Baltic Sea. The soil-structure interaction is idealized as a set of linear translational and rotational springs. Due...
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Determinants of Firm Innovation in Indonesia: The Role of Institutions and Access to Finance
PublicationThis paper investigates the determinants of firm innovation in Indonesia. Using quality of local regulations index constructed by the Indonesia’s Regional Autonomy Watch (KPPOD) as measure of institutions, We found that better institutional quality at the local level was associated with more innovation and that firms experiencing major obstacle in access to finance were less likely to innovate. Access to finance is more critical...
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Fire-Retardant Flexible Foamed Polyurethane (PU)-Based Composites: Armed and Charmed Ground Tire Rubber (GTR) Particles
PublicationInadequate fire resistance of polymers raises questions about their advanced applications. Flexible polyurethane (PU) foams have myriad applications but inherently suffer from very high flammability. Because of the dependency of the ultimate properties (mechanical and damping performance) of PU foams on their cellular structure, reinforcement of PU with additives brings about further concerns. Though they are highly flammable and...
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Structure and properties comparison of poly(ether-urethane)s based on nonpetrochemical and petrochemical polyols obtained by solvent free two-step method
PublicationThe application of thermoplastic polyurethanes (TPU) is becoming more and more extensive, and the decreasing of used petrochemical monomers and reduction of energy for the polymerization and processing processes is getting increasingly important. In this paper, we confirmed the positive influence of high bio-based monomers contents (by replacing petrochemical polyol and glycol by bio-based counterparts) on processing and properties...
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Opto-Electrochemical Sensing Device Based on Long-Period Grating Coated with Boron-Doped Diamond Thin Film
PublicationThe fabrication process of thin boron-doped nanocrystalline diamond (B-NCD) microelectrodes on fused silica single mode optical fiber cladding has been investigated. The B-NCD films were deposited on the fibers using Microwave Plasma Assisted Chemical Vapor Deposition (MW PA CVD) at glass substrate temperature of 475 ºC. We have obtained homogenous, continuous and polycrystalline surface morphology with high sp3 content in B-NCD...
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CONSUMERS’ APPROACH TO THE CREDIBILITY OF THE INFLATION FORECASTS PUBLISHED BY CENTRAL BANKS: A NEW METHODOLOGICAL SOLUTION
PublicationModern monetary policy focuses on credibility and shaping inflation expectations. In keeping with the concept of inflation forecast targeting, the inflation forecasts published by central banks play a crucial role in the instrument rate decision-making process and may be treated as a specific intermediate target. This study proposes an inflation forecast credibility index, the scope of which is narrowed to non-specialists’ approach...
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The Emergence of ETFs in Asia-Pacific
PublicationThe major objective of this book is to contribute to the present state of knowledge by exploring empirical links between the processes of diffusion of financial innovations— exchange-traded funds—and growing deployment of ICT across Asia-Pacific countries, between 2004 and 2017. We examine the evolutionary patterns of ETFs on selected Asia-Pacific stock exchanges and verify the hypothesized relationship between increasing ICT penetration...
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WYDATKI INWESTYCYJNE WOJEWÓDZTW SAMORZĄDOWYCH PO WPROWADZENIU INDYWIDUALNEGO WSKAŹNIKA ZADŁUŻENIA
PublicationOkreślenie dopuszczalnego poziomu zadłużenia jest ważną kwestią dla każdej jednostki samorządu terytorialnego w Polsce, a jej ranga jeszcze rośnie, jeśli samorząd odczuwa silną presję na dbanie o rozwój obszaru, na którym funkcjonuje, borykając się równocześnie z niedostatkiem dochodów. Taka sytuacja dotyczy większości województw samorządowych, które spośród wszystkich szczebli struktury samorządowej...
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Multicultural coastal cities: what are the differences in culture of urban planning management. Comparison analysis of Gdańsk and Gdynia
PublicationThe goal of this book chapter is the analysis of the multiculturalism of the seaside cities (Gdansk and Gdynia). We define multiculturalism by ethnic aspects, as concentration of multiple nationalities and ethnic groups over the given area and non ethnic aspects, as occurrence of multiple symbols, signs or cultures. We sense multiculturalism of the cities through the cultural and social properties of the citizens and urban architecture....
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One Europe, one product, two prices - the price disparity in the EU
PublicationThe price dispersion in the European Union in the last fifteen years (1990-2005) is analysed. The analysis of price convergence is examined on aggregate and disaggregate levels. The macro approach is based on Comparative Price Level index calculated as the ratio between PPPs and exchange rate. The disaggregate analysis utilizesactual prices of 148 individual products sold in the 15 capital cities of the EU. The calculations comprise...
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Influence of Thermal Decomposition of Wood and Wood-Based Materials on the State of the Atmospheric Air. Emissions of Toxic Compounds and Greenhouse Gases
PublicationThis paper presents the energy characteristics of wood and wood-based materials in the form of commercially available pellets, furniture board (MDF) and OSB. Toxicometric indices were determined for gaseous destructs arising from thermal decomposition and combustion of the materials studied. The paper proves that combustion conditions are crucial in terms of toxic destructive emissions. It has been shown that the combustion of...
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The conditions of the business services sector in Poland and its competitiveness in the global market
PublicationThe following article presents the conditions of the business services sector (BSS) in Poland and the assessment of its competitiveness in the global market. The first section discusses the BSS sector and the categories of the provided services, in the division of business process outsourcing, shared services center, information technology outsourcing, research and development. Next the authors presents the status of the business...
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Facing the brainstorming theory. A case of requirements elicitation
PublicationKnowledge is still considered to be power and its externalization makes it possible for others to use that power. In this paper, we examine the theory of brainstorming, and the claim by father Alex Osborn that in a group session an individual can think of twice as many ideas than working alone. In the context of requirements elicitation, we performed an experiment on a “nominal” and a “real” group of participants, following a procedure...