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Search results for: GEOCHEMICAL AND PETROLOGICAL CHARACTERISTICS
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The role of slowly biodegradable substrate in a full-scale biological nutrient removal activated sludge systems
PublicationThis paper contains futher results obtained at ''Wschod'' WWTP in Gdańsk under transient conditions (spring season) and comparation of similar experiments carried out at a recently upgraded ''Debogorze'' WWTP in Gdynia. The removal of colloidal and particulate fractions resulted in similar effects (reduced process rates) at both plants. For example, the initial denitrification rates (NUR1) were up to 30% lower during the ''conventional''...
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Traffic Noise Analysis Applied to Automatic Vehicle Counting and Classification
PublicationProblems related to determining traffic noise characteristics are discussed in the context of automatic dynamic noise analysis based on noise level measurements and traffic prediction models. The obtained analytical results provide the second goal of the study, namely automatic vehicle counting and classification. Several traffic prediction models are presented and compared to the results of in-situ noise level measurements. Synchronized...
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Comparison of selected electroencephalographic signal classification methods
PublicationA variety of methods exists for electroencephalographic (EEG) signals classification. In this paper, we briefly review selected methods developed for such a purpose. First, a short description of the EEG signal characteristics is shown. Then, a comparison between the selected EEG signal classification methods, based on the overview of research studies on this topic, is presented. Examples of methods included in the study are: Artificial...
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Selected studies of flow maldistribution in a minichannel plate heat exchanger
PublicationAnalysis of the state of-the-art in research of minichannel heat exchangers, especially on the topic of flow maldistribution in multiple channels, has been accomplished. Studies on minichannel plate heat exchanger with 51 parallel minichannels with four hydraulic diameters, i.e., 461 μm, 574 μm, 667 μm, and 750 μm have been presented. Flow at the instance of filling the microchannel with water at low flow rates has been visualized. The...
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The mechanism of grouting action under the base of bored pile
PublicationThe grouting under the base of bored pile is carried out in order to reduce pile settlement and improve its bearing capacity. The principal aim of grouting is to introduce an initial force between the soil and the pile base. In non-cohesive soil, the grouting can also enlarge the pile base area and therefore improve the base resistance. The example of static load tests on instrumented bored piles installed with and without grouting...
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Examination of the factors influencing binaural rendering on headphones with the use of directivity patterns
PublicationThis paper presents a study on the influence of the directional sound sources with the use of the directivity patterns. This contribution also includes a comparison to the work done by Wendt et al., where several directivity pattern designs used to gradually control the auditory source distance in a room were showed. While the tests of Wendt et al. were done by auralizing source and room using a loudspeaker ring in an anechoic...
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Identification of diagnostic parameter sensitivity during dynamic processes of a marine engine
PublicationChanging some parameters of the engine structure alters the emission of harmful components in the exhaust gas. This applies in particular to the damage of charge exchange system as well as fuel system and engine supercharger. These changes are much greater during the dynamic states and their accompanying transitional processes. The different sensitivity of diagnostic parameters to the same force, coming from the engine structure, but...
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IZOLACJA I IDENTYFIKACJA NATURALNYCH SUBSTANCJI BARWIĄCYCH OBECNYCH W PRÓBKACH FARB ARTYSTYCZNYCH I TKANINACH POCHODZENIA HISTORYCZNEGO
PublicationNatural organic dyes are group of substances that belong to various types of chemical compounds. The most commonly used in paintings and dyeing textiles were naturally occurring dyestuffs from group of anthraquinones, flavones and indigoid dyes. Identification of coloring substances present in historical artistic paints provides relevant information for a wide range of specialists dealing with works of art and in the field of conservation science....
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The Impact of Trade Integration with the European Union on Productivity in a Posttransition Economy: The Case of Polish Manufacturing Sectors
PublicationThis paper addresses the relationship between productivity growth in Polish manufacturing sectors and forces stemming from trade integration with the European Union. Empirical analysis (1995-2006) is based on sector-level bilateral data concerning both domestic (Polish) and foreign (partner countries from the enlarged European Union) markets' characteristics and their degree of openness. The main results indicate that, both in...
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Fundamentals of Communication Networks Resilience to Disasters and Massive Disruptions
PublicationCommunication networks are exposed to a variety of massive failure events following from activities of nature, weather-induced disruptions, technology-implied problems, and malicious human activities. In this chapter, we first highlight the characteristics of these scenarios and discuss example failure events reported during the last three decades. Next, we explain the concept of network resilience and present an overview of major...
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Obtaining of coumarone-indene resins based on light fraction of coal tar 2. Coumarone-indene resins with epoxy groups
PublicationCoumarone-indene resins (CIR) with carboxy groups were synthesized via cooligomerization of unsaturated compounds presented in light fraction of coal tar and its fraction boiling out within 423–463 K with the addition of such industrial monomers as styrene, maleic anhydride, glycidyl methacrylate and methacrylic acid. 2,2`-Azobis(2-methylpropionitrile) in the form of 0.2 M solution in toluene was used as an initiator. The effect...
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Prevention of resonance oscillations in gear mechanisms using non-circular gears
PublicationOne of the main disadvantages of gear mechanisms is the occurrence of noise and vibrations. This study investigated the applicability of non-circular gears for preventing resonance oscillations in gear mechanisms. The influence of a small deviation of the gear centrodes from the nominal circles on kinematic and oscillatory characteristics was analysed. It was shown that a larger deviation results in a smaller resonance amplitude...
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Novel Low-Loss Substrates for 5G Applications
PublicationThis paper presents a feasibility study of a new type of microwave low-loss dielectric substrates for 5G network applications. The new substrate materials are composites of polypropylene and high-dielectric-constant micro-ceramics. This combination is expected to form a very low-loss dielectric material at low fabrication cost. Two substrate samples with different dielectric properties are fabricated and their characteristics at...
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Experimental study of the multi-disc negative brake for a hydraulic motor
PublicationThis paper describes the methodology for experimental testing of a multi-disc brake. The construction of this brake was also present. The brake is dedicated to hydraulic motors with a small working volume. Experimental tests were carried out on a brake with plates immersed in oil and, for comparison, tests were carried out on a dry brake. As a result of the tests, the permissible torque (load) that is able to transfer the brake...
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Mechanizm współpracy z gruntem pali prefabrykowanych wbijanych w świetle próbnych obciążeń pali oprzyrządowanych
PublicationOpis badań i wyniki próbnych obciążeń statycznych dwóch pali prefabrykowanych wbijanych oprzyrządowanych w aparaturę do pomiaru rozkładu siły osiowej wzdłuż trzonu pala. Analiza wpływu czasu i procesu wbijania na charakterystykę osiadania pali prefabrykowanych wbijanych. Identyfikacja siły rezydualnej w palu prefabrykowanym wbijanym i jej wpływ na interpretację pomiarów ekstensometrycznych w próbnym obciążeniu pala. Wnioski na...
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Enzyme-conjugated MXene nanocomposites for biosensing and biocatalysis acuities
PublicationEngineered two-dimensional (2-D) MXenes-based materials with tunable characteristics and multi-functionalities have brought up new paradigms in the biosensing and catalysis of chemical compounds. The profusion of electroactive functional moieties on the surface of few/multi-layer MXenes facilitates their ability to retain biomolecules such as enzymes resulting in unique dimensions for bioanalytical and biosensing applications....
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An advanced tool integrating failure and sensitivity analysis into novel modeling of the stormwater flood volume
PublicationAn innovative tool for modeling the specific flood volume was presented that can be applied to assess the need for stormwater network modernization as well as for advanced flood risk assessment. Field measurements for a catchment area in Kielce, Poland, were used to apply the model and demonstrate its usefulness. This model extends the capability of recently developed statistical and machine learning hydrodynamic models developed...
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Automatic recognition of males and females among web browser users based on behavioural patterns of peripherals usage
PublicationPurpose The purpose of this paper is to answer the question whether it is possible to recognise the gender of a web browser user on the basis of keystroke dynamics and mouse movements. Design/methodology/approach An experiment was organised in order to track mouse and keyboard usage using a special web browser plug-in. After collecting the data, a number of parameters describing the users’ keystrokes, mouse movements and clicks...
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Effect of the integration into Global Value Chains on the employment contract in Central and Eastern European countries
PublicationResearch background: In the era of globalization, there is a need to address decent work deficits in Global Value Chains (GVCs). The forms of working conditions reveal a broad dispersion of contents. The literature review exposes hardly any Europe-focused research assessing the socioeconomic impact of global production links and going beyond their pure economic effects assessed in terms of employment, productivity or wages. Purpose...
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Hałaśliwość silników asynchronicznych – podstawy nowych hipotez
PublicationArtykuł zawiera nowe spojrzenie na hałas emitowany przez silniki asynchroniczne. Poprzez wykonane badania akustyczne z analizami widmowymi określono związki przyczynowo-skutkowe powstawania drgań i hałasu przy zasilaniu sieciowymch i przekształtnikowym. Na podstawie wyznaczonych charakterystyk kierunkowych ciśnienia akustycznego silników sformułowano hipotezę, że rola tarcz łożyskowych w emitowaniu hałasu przez silnik może być...
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Review and Indication of Key Activities for Energy Management Improvement in DC Microgrids
PublicationDC MicroGrids (MG) must have Energy Management Systems (EMS) to guarantee efficient, dependable, and environmentally friendly electricity. The application of Model Predictive Control (MPC), proved to be helpful due to its adaptability and capacity to use non-linear models. This paper, based on an extensive literature review, identifies and discusses the three key activities to improve the characteristics of DC microgrids, i.e.:...
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Fashion and Tourism: Parallel Stories of Two "Dream Marvels".
PublicationFashion and tourism are two social, cultural, and economic phenomena that have both numerous connections and surprising similarities. These are not new: they have been built and developed since the beginnings of tourism as a modern social phenomenon, emerged in Europe in the context of the industrial revolution. They consolidated in the first decades of the 21st century, in a context where both phenomena have completed their “mass”...
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Multicomponent layers for aluminium alloys surface consolidation
PublicationThe main reason of the surface modification of the components such as pistons and cylinder blocks made of cast aluminium alloys is to obtain high hardness, wear and corrosion resistance of the working surface for larger lifetime of the motor-car and aircraft engines. In that aspect, the new conception of development - by hybrid method - of surface layers containing manganese, nitrogen, sulphur (Mn-N-S) and manganese, nitrogen,...
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GROUP COMPOSER - System for Modeling Agents’ Team Building for Tasks
PublicationMulti-agent systems consist of many autonomous units, called agents, that can interact when trying to achieve their goals. The selection of interaction partners is called team formation. Three basic approaches can be considered to match multi-agent system resources to the problem at hand. To research the properties of different approaches, a software for modeling team formation in multi-agent systems has been created and is presented...
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Estimation of the steam condensation flow via CFD methods
PublicationThe results of numerical simulations to predict the performance of different steam models have been presented. All of the considered models of steam condensation have been validated on the base of benchmark experiment employing expansion in nozzle and next on the low pressure part of the steam turbine stage. For numerical analysis three models have been finally used – the ideal steam model without condensation, an equilibrium steam...
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Examining Acoustic Emission of Engineered Ultrasound Loudspeakers
PublicationMeasurement results of the sound emitted from an ultrasound custom-made system with high spatial directivity are presented. The proposed system is using modulated ultrasound waves which demodulate in nonlinear medium resulting in audible sound. The system is aimed at enhancing the users’ personal audio space, therefore the measurements are performed using the Head and Torso Simulator which provides the realistic reproduction of...
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Content-Based Approach to Automatic Recommendation of Music
PublicationThis paper presents a content-based approach to music recommendation. For this purpose, a database which contains more than 50000 music excerpts acquired from public repositories was built. Datasets contain tracks of distinct performers within several music genres. All music pieces were converted to mp3 format and then parameterized based on MPEG-7, mel-cepstral and time-related dedicated parameters. All feature vectors are stored...
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Re-thinking the city in the context of suburban landscapes. The case of Visula River delta water - landscapes and urban transformation processes in Gdańsk
PublicationThe text draws attention to the significant role of landscape formations surrounding the city and their role in marking out directions for the transformation and development of urban areas with the particular emphasis on public spaces. The article presents the need for a more conscious design strategies that are based on connectedness of urban spaces, which is built on landscape's characteristics, as an essential starting point...
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TOTAL SHIP OPERABILITY – REVIEW, CONCEPT AND CRITERIA
PublicationThe ship operability can be understood and analysed in different manners, and its quality is described using different indexes by different authors. Practically, there is no general and widely accepted description of total ship operability in the literature, nor in the rules of classification societies, which would include both seakeeping and manoeuvrability characteristics of a ship, and simultaneously take into account all ship...
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Speed management on local government managed roads – research, recommendations and guidelines
PublicationCommissioned by the National Road Safety Council Secretariat, the project “Guidelines for speed management on local government managed roads” studied car driver be haviour when subjected to selected speed management measures such a local speed restrictions, surveillance, traffic calming and restricted speed areas. In addition, analyses were conducted on the impact of selected me asures...
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Electronic Noses for Indoor Air Quality Assessment
PublicationThis chapter presents a proposal of the use of electronic noses in the monitoring of indoor air quality. The main focus is put on the detailed characteristics of today’s indoor air quality control methods, the types of pollution in the air, and the development of electronic noses for air testing. Currently, scientists seek methodological and structural solutions that would enable real-time online indoor air control. It has been...
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OBTAINING OF COUMARONE-INDENE RESINS BASED ON LIGHT FRACTION OF COAL TAR 3. COUMARONE-INDENE RESINS WITH METHACRYLIC FRAGMENTS
PublicationThe method for obtaining coumarone-indene resins with methacrylic fragments (CIRM) was developed with the addition of methyl ethacrylate, using a light fraction of coal tar and its fraction boiling within 423–463 К. CIRM was obtained via radical cooligomerization using 2,2'-azobis (2-methyl-propionitrile) as the initiator. The effect of the initiator amount, temperature and reaction time on the yield, softening temperature and...
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Estimation of a Stochastic Burgers' Equation Using an Ensemble Kalman Filter
PublicationIn this work, we consider a difficult problem of state estimation of nonlinear stochastic partial differential equations (SPDE) based on uncertain measurements. The presented solution uses the method of lines (MoL), which allows us to discretize a stochastic partial differential equation in a spatial dimension and represent it as a system of coupled continuous-time ordinary stochastic differential equations (SDE). For such a system...
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On the impact of Big Data and Cloud Computing on a scalable multimedia archiving system
PublicationMultimedia Archiver (MA) is a system build upon the promise and fascination of the possibilities emerging from cloud computing and big data. We aim to present and describe how the Multimedia Archiving system works for us to record, put in context and allow a swift access to large amounts of data. We introduce the architecture, identified goals and needs taken into account while designing a system processing data with Big Data...
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Obtaining of Coumarone-Indene Resins Based on Light Fraction of Coal Tar. 4. Bitumen-Polymer Blends with Participation of Coumarone-Indene Resins with Epoxy Groups
PublicationUsing light fraction of coal tar (5.75 wt % of coumarone and 44.45 wt % of indene), glycidyl methacrylate and styrene, the coumarone-indene resin with epoxy groups (CIRE) has been synthesized. Monoperoxy derivative of diglycidyl ether Bisphenol A (PO) was used as an initiator. The possible formation of CIRE has been studied on the model systems consisting of PO, glycidyl methacrylate, indene or coumarone, or styrene, or mixture...
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Can we rely on the pulse transit time - pressure relationship - models comparison
PublicationAn unobtrusive, noninvasive and continuous pressure measurement is invaluable however, still being under research and development. There are many attempts proposing an appropriate relationship between pulse pressure velocity and pressure. Fifteen different formulas, both theoretical and experimental, describing relation between blood pressure and crosssectional area of the vessel were examined. Using these formulas the relation...
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MODEL OF MULTILEVEL STOCHASTIC ANALYSIS OF ROAD SAFETY ON REGIONAL LEVEL
PublicationIn this paper multilevel approach to the issue of road safety level on the road network of European regions, classified as NUTS 2 in statistical databases of the European Union, has been presented. Following the pattern of many publications on road safety it has been assumed that the risk calculated as the number of death casualties in road accidents per 100,000 inhabitants of a given region has Poisson distribution. Therefore,...
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AUDIO SIGNAL EQUALIZATION BASED ON IMPULSE RESPONSE OF A LISTENING ROOM AND MUSIC CONTENT REPRODUCED
PublicationA research study presents investigations of the influence of the room acoustics on the frequency characteristic of the audio signal playback. First, a concept of a novel spectral equalization method of the room acoustic conditions is introduced. On the basis of the room spectral response, a system for room acoustics compensation based on an equalizer designed is proposed. The system settings depend on music genre recognized automatically....
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Mid-infrared spectroscopy for characterization of Baltic amber (succinite)
PublicationNatural Baltic amber (succinite) is the most appreciated fossil resin of the rich cultural traditions dating back to prehistoric times. Its unequivocal identification is extremely important in many branches of science and trades including archeology, paleontology, chemistry and finally mineralogical and gemological societies. Current methods of modification of natural succinite are more and more sophisticated making the identification...
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Arctic Freshwater Environment Altered by the Accumulation of Commonly Determined and Potentially New POPs
PublicationChemical composition of Arctic freshwater ecosystems depends on several factors. They include characteristics of the surrounding landscape, its lithology, geomorphology, vegetation, and hydrological features, as well as accumulation of anthropogenic pollution. In the Arctic, the problem of environmental contamination is widespread. That is why research on lakes and river catch-ments in terms of their chemical composition has enjoyed...
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In Situ Verification of Numerical Model of Water Hammer in Slurries
PublicationThis paper presents a numerical model of transient flow in a pressure slurry pipeline network with verification based on in situ measurements. The model, primarily verified in laboratory conditions, has been extended and applied to the case of a large and complex slurry pipeline network in Poland. In the model, the equivalent density concept was applied. In situ experiments were performed for various unsteady flow episodes, caused by...
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High Performance Tubular Heat Exchanger with Minijet Heat Transfer Enhancement
PublicationIn the paper, the original cylindrical heat exchanger with minijets (MJHE) was introduced. The systematic experimental analysis of the prototype heat exchanger was described with special attention paid to such parameters as the heat transfer effectiveness, heat transfer rates, overall heat transfer coefficients, and pressure drop. The heat transfer coefficients were determined based on Wilson plot method, the most suitable approach...
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Promising Nanoparticle-Based Heat Transfer Fluids—Environmental and Techno-Economic Analysis Compared to Conventional Fluids
PublicationProviding optimal operating conditions is one of the major challenges for effective heating or cooling systems. Moreover, proper adjustment of the heat transfer fluid is also important from the viewpoint of the correct operation, maintenance, and cost efficiency of these systems. Therefore, in this paper, a detailed review of recent work on the subject of conventional and novel heat transfer fluid applications is presented. Particular...
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Negative Poisson’s ratio from pentagons: A new auxetic structure combining three different auxetic mechanisms
PublicationA novel class of two-dimensional auxetic structures based on the pentagon motif is proposed. Their mechanical properties are investigated by combining molecular mechanics simulations with a simple three-parameter mechanical model which assumes perfectly elastic behavior. It is predicted that the proposed structures – termed as double re-entrant honeycomb – may possess unique mechanical characteristics, which include complete and...
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Fundamenty palowe, obliczenia z zastosowaniem zasad Eurokodu 7 i doświadczeń krajowych
PublicationPrzedstawiono zagadnienia obliczania fundamentów palowych w nawiązaniu do zaleceń Eurokodu 7. Zwrócono uwagę, że zgodnie z założeniami Eurokodu 7, projektant i inżynier ma swobodę w wyborze metod obliczeniowych.Przytoczono i zarekomendowano metody i propozycje miedzy innymi obliczania statycznego układów palowych, określania nośności pali, prognozowania osiadań fundamentów palowych oraz charakterystyk obciążenie-osiadanie pali...
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Database of the illustrative simulations of the nonstandard approximation of the generalized Burgers–Huxley equation
Open Research DataThe presented dataset is a result of numerical analysis of a generalized Burgers–Huxley partial differential equation. An analyzed diffusive partial differential equation consist with nonlinear advection and reaction. The reaction term is a generalized form of the reaction law of the Hodgkin–Huxley model, while the advection is a generalized form of...
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The Chow Ring of flag manifolds
Open Research DataSchubert calculus is the intersection theory of 19th century. Justifying this calculus is the content of the 15th problem of Hilbert. In the course to establish the foundation of algebraic geometry, Van der Vaerden and A. Weil attributed the problem to the determination of the chow ring of flag manifolds G/P, where G is a compact Lie group and P is...
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Defense mechanisms and borderline personality organization among COVID-19 believers and non-believers during complete lock-down
PublicationThe aim of the current study was to investigate whether a specific social perception of the pandemic—believing or not in COVID-19—predicts borderline personality organizations and whether this relationship is mediated by more primitive maladaptive mechanisms—splitting, denial, and dissociation. The online study included 720 organization aged 25–45. Participants were diverse in terms of place of residence, being in a relationship,...
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Practical Approach to IP Scheduled Throughput Measurements in Dual Connectivity Systems
PublicationIP scheduled throughput defined according to 3GPP TS 36.314 reflects user throughput regardless of traffic characteristics, and therefore has become one of the most important indicators for monitoring Quality of Service (QoS) of the end user in Evolved Universal Terrestrial Radio Access Network (E-UTRAN). However, networks built on a distributed architecture make the above definition impossible to be applied directly due to the...
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The effect of preliminary creep-strain on material behavior under LCF tension/compression and pure torsion regimes
PublicationThis paper presents the results of experimental tests of monotonic tension and torsion, creep-rupture and preliminary creep at 200C and 300C, as well as low-cycle fatigue of 2024 T3511 aluminum alloy. The fatigue process was conducted at room temperature for uniaxial tension/compression and torsion. The as-received material and pre-deformed material were also investigated during creep at elevated temperature. Basic monotonic,...