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Wyniki wyszukiwania dla: PASSIVE HIP MOMENT
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A New Approach to Assess Quality of Motion in Functional Task of Upper Limb in Duchenne Muscular Dystrophy
Publikacja(1) Background: This study presents a new method for the motion quantitative analysis of Duchenne muscular dystrophy patients (DMD) performing functional tasks in clinical conditions. (2) Methods: An experimental study was designed to define how different levels of external mass (light and heavy) influence the performance of the upper limbs of a tested DMD and reference subject (RS) during horizontal movements (level of the waist)...
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Biocompatibility and bioactivity of load-bearing metallic implants
PublikacjaThe main objective of here presented research is to develop the titanium (Ti) alloy base composite materials possessing better biocompatibility, longer lifetime and bioactivity behaviour for load-bearing implants, e.g. hip joint and knee joint endoprosthesis. The development of such materials is performed through: modeling the material behaviour in biological environment in long time and developing of new procedures for such evaluation;...
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Unravelling the role of electron–hole pair spin in exciton dissociation in squaraine-based organic solar cells by magneto-photocurrent measurements
PublikacjaA high absorption coefficient and narrow absorption bands in squaraine (SQ) dyes have resulted in rapidly growing interest in them as a donor material in photovoltaic devices. The exciton dissociation process in organic systems proceeds via a multistep mechanism where the electron–hole pairs (charge transfer states) involved in the current generation process determine the recombination losses and subsequently limit the overall...
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Fast Multi-Objective Aerodynamic Optimization Using Sequential Domain Patching and Multifidelity Models
PublikacjaExploration of design tradeoffs for aerodynamic surfaces requires solving of multi-objective optimization (MOO) problems. The major bottleneck here is the time-consuming evaluations of the computational fluid dynamics (CFD) model used to capture the nonlinear physics involved in designing aerodynamic surfaces. This, in conjunction with a large number of simulations necessary to yield a set of designs representing the best possible...
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eFRADIR: An Enhanced FRAmework for DIsaster Resilience
PublikacjaThis paper focuses on how to increase the availability of a backbone network with minimal cost. In particular, the new framework focuses on resilience against natural disasters and is an evolution of the FRADIR/FRADIR-II framework. It targets three different directions, namely: network planning, failure modeling, and survivable routing. The steady state network planning is tackled by upgrading a sub-network (a set of links termed...
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Biomechanics of Lumbar Spine Injury in Road Barrier Collision–Finite Element Study
PublikacjaLiterature and field data from CIREN database have shown that lumbar spine injuries occur during car crashes. There are multiple hypotheses regarding how they occur; however, there is no biomechanical explanation for these injuries during collisions with road safety barriers (RSBs). Therefore, the objective of this study was to investigate the mechanics of vertebral fractures during car collisions with concrete RSBs. The finite...
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Fragility analysis of structural pounding between adjacent structures arranged in series with various alignment configurations under near‑field earthquakes
PublikacjaA major cause of local to total damages is related to structural pounding in a large number of past earthquakes. In general, these collisions take place as a result of differences in the dynamic characteristics of the colliding structures. To acquire a better perception of the behavior of structures, in this paper, three structures featuring different heights are modeled in series and with various configurations next to each other...
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Probabilistic assessment of SMRFs with infill masonry walls incorporating nonlinear soil-structure interaction
PublikacjaInfill Masonry Walls (IMWs) are used in the perimeter of a building to separate the inner and outer space. IMWs may affect the lateral behavior of buildings, while they are different from those partition walls that separate two inner spaces. This study focused on the seismic vulnerability assessment of Steel Moment-Resisting Frames (SMRFs) assuming different placement of IMWs incorporating nonlinear Soil-Structure Interaction (SSI)....
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Seismic performance evaluation of steel buckling-restrained braced frames including SMA materials
PublikacjaThe permanent deformation of the building after seismic excitations can be determined by the Maximum Residual Interstory Drift Ratio (MR-IDR), which may be used for measuring the damage states. Low-post yield stiffness of the steel buckling-restrained braced frame (BRBF) makes this system vulnerable to large MR-IDR after a severe earthquake event. To overcome this issue, this paper investigates the seismic limit state performances...
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Predicting the seismic collapse capacity of adjacent SMRFs retrofitted with fluid viscous dampers in pounding condition
PublikacjaSevere damages of adjacent structures due to structural pounding during earthquakes have emphasized the need to use some seismic retrofit strategy to enhance the structural performance. The purpose of this paper is to study the influence of using linear and nonlinear Fluid Viscous Dampers (FVDs) on the seismic collapse capacities of adjacent structures prone to pounding and proposing modification factors to modify the median...
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Application of different building representation techniques in HEC-RAS 2-D for urban flood modeling using the Toce River experimental case
PublikacjaThis paper presents the impact of the choice of building representation techniques and hydrodynamic models on urban flood simulations using HEC-RAS 2-D for the Toce River physical model. To this end, eight numerical models based on previous laboratory experiments were prepared to simulate unsteady urban flooding on each side of building units. Two simplified building layouts (aligned and staggered) were examined, where models were...
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ENERGY ANALYSIS OF PROPULSION SHAFT FATIGUE PROCESS IN ROTATING MECHANICAL SYSTEM PART I TESTING SIGNIFICANCE OF INFLUENCE OF SHAFT MATERIAL FATIGUE EXCITATION PARAMETERS
PublikacjaThe article discusses the problem of mathematical modelling of energy conversion processes in a rotating mechanical system for the purpose of identifying fatigue states of propulsion shafts in this system. A simplified physical model of the analysed system, constructed in an appropriate scale, has made the basis for the experimental research. The research programme took into consideration mechanical fatigue excitation of the model...
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Acoustic radar employing particle velocity sensors
PublikacjaA concept, practical realization and applications of a passive acoustic radar to automatic localization, tracking of sound sources were presented in the paper. The device consist of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. Contrary to active radars, it does not emit the scanning beam but after receiving surroundings sounds it provide information about the...
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Miniaturization of ESPAR Antenna Using Low-Cost 3D Printing Process
PublikacjaIn this paper, the miniaturized electronically steerable parasitic array radiator (ESPAR) antenna is presented. The size reduction was obtained by embedding its active and passive elements in polylactic acid (PLA) plastic material commonly used in low-cost 3D printing. The influence of 3D printing process imperfections on the ESPAR antenna design is investigated and a simple yet effective method to...
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BTEX concentration levels in urban air in the area of the Tri-City agglomeration (Gdansk, Gdynia, Sopot), Poland
PublikacjaThe paper presents and discusses the results of atmospheric air quality research conducted in 2012 with reference to the level of BTEX compounds in the Tri-City agglomeration—Gdansk, Gdynia, and Sopot (northern Poland). At the stage of BTEX sampling from the ambient air, Radiello® diffusive passive samplers were applied. The annual time-weighted average concentrations for benzene, toluene, ethylbenzene, and xylenes (BTEX) in the...
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Greedy Multipoint Model-Order Reduction Technique for Fast Computation of Scattering Parameters of Electromagnetic Systems
PublikacjaThis paper attempts to develop a new automated multipoint model-order reduction (MOR) technique, based on matching moments of the system input–output function, which would be suited for fast and accurate computation of scattering parameters for electromagnetic (EM) systems over a wide frequency band. To this end, two questions are addressed. Firstly, the cost of the wideband reduced model generation is optimized by automating a...
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Cost-Efficient Optical Fronthaul Architectures for 5G and Future 6G Networks
PublikacjaFifth-generation and Beyond (5GB) wireless networks have introduced new centralized architectures such as cloud radio access network (CRAN), which necessitate extremely high-capacity low latency Fronthaul (FH). CRAN has many advantageous features in terms of cost reduction, performance enhancement, ease of deployment, and centralization of network management. Nevertheless, designing and deploying a cost-efficient FH is still a...
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Recent Advances in Loop Heat Pipes with Flat Evaporator
PublikacjaThe focus of this review is to present the current advances in Loop Heat Pipes (LHP) with flat evaporators, which address the current challenges to the wide implementation of the technology. A recent advance in LHP is the design of flat-shaped evaporators, which is better suited to the geometry of discretely mounted electronics components (microprocessors) and therefore negate the need for an additional transfer surface (saddle)...
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Direction of Arrival Estimation Based on Received Signal Strength Using Two-Row Electronically Steerable Parasitic Array Radiator Antenna
PublikacjaIn this paper, we present a novel approach to direction-of-arrival (DoA) estimation using two-row electronically steerable parasitic array radiator (ESPAR) antenna which has 12 passive elements and allows for elevation and azimuth beam switching using a simple microcontroller, relying solely on received signal strength (RSS) values measured at the antenna output port. To this end, we thoroughly investigate all 18 available 3D antenna...
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Comparative analysis of the flow control over a circular cylinder with detached flexible and rigid splitter plates
PublikacjaA comparative study is performed on a circular cylinder with both flexible and rigid splitter plates (SPs). This study has the novelty of using single and dual detached SPs located downstream of the cylinder. The dimensionless gap distance between the first splitter plate and the cylinder as well as the distance between the SPs are varied. The strain of flexible SPs can be used for energy harvesting from the flow. Therefore, a...
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The Handling of Business Lawsuits by Common Courts in Poland: Identification of Transaction Costs
PublikacjaCelem artykułu jest identyfikacja czynników mających wpływ na koszty transakcyjne dochodzenia praw z umów pomiędzy przedsiębiorcami w sprawach gospodarczych. Na potrzeby artykułu przeprowadzono pilotażowe badanie 210 spraw sądowych zawisłych przed Sądem Okręgowym w Gdańsku w pierwszej instancji po 2009 r., w których wyrok wydano w 2012 r. (ostatnie 210 spraw) a od wyroku wniesiono apelację do Sądu Apelacyjnego w Gdańsku i zakończono...
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Charge Distribution and Hyperfine Interactions in GdBa2Cu3O7 from First Principles
PublikacjaW rozdziale przedstawiono wyniki obliczeń "z zasad pierwszych" (''ab initio'') struktury elektronowej, rozkładu ładunku i struktury nadsubtelnej, w szczególności gradientu pola elektrycznego (EFG) i składnika kontaktowego pola nadsubtelnego (HFF), nadprzewodnika wysokotemperaturowego o wzorze GdBa2Cu3O7 (Gd123). Do obliczeń wykorzystano metodę FP-LAPW (full-potential linearized augmented plane wave). Efekty związane z oddziaływaniami...
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Europe, between Mandatory and Voluntary Approach to CSR: Some New Evidence from the Polish Listed Companies
PublikacjaThis paper aims to explore the relationship between corporate governance rules and application of CSR practices into operations of the top 30 companies listed on the Warsaw Stock Exchange. Since in Poland, so far, there is no obligation to follow any specific CSR standards or to make disclosures of non-financial, social and environmental information, this is still a fully voluntary approach. At the moment, only some of the companies...
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Optical and photocatalytic properties of rare earth metal-modified ZnO quantum dots
PublikacjaA series of novel ZnO quantum dots modified with rare earth metals was successfully prepared by a simple sol-gel approach. The effects of types (Eu, Er, Tb, Yb, Ho, La) and amounts (from 0.09 to 0.45 mmol) of lanthanides on the optical properties, structural characterization and photocatalytic activity of ZnO/RE QDs were systematically investigated. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform...
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Pharmaceuticals and another groups of emerging contaminants: Occurrence and sources in Admiralty Bay (King George Island, Maritime Antarctica)
PublikacjaEveryday live activities may introduce a wide range of chemicals into wastewater systems. In this study presence of selected types of pharmaceuticals from cardiovascular system group, nervous and muscolo-skeleton system group, antimicrobial agents, genitourinary and sex hormones were tested in the wastewater from H. Arctowski Antarctic station. Moreover, the receiver of discharged wastewater (Admiralty Bay) were also studied. Considering...
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Enhancing seismic performance of rigid and semi-rigid connections equipped with SMA bolts incorporating nonlinear soil-structure interaction
PublikacjaNowadays, using smart connections can improve the performance of buildings with some recentering features that are from the superelastic behavior of Shape Memory Alloys (SMAs). It seems that there is different rigidity between the designed connection and the real one in Steel Moment-Resisting Frames (SMRFs), which can be considered as a problematic issue due to the importance of connections in seismic performance assessment. This...
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Computationally Efficient Design Optimization of Compact Microwave and Antenna Structures
PublikacjaMiniaturization is one of the important concerns of contemporary wireless communication systems, especially regarding their passive microwave components, such as filters, couplers, power dividers, etc., as well as antennas. It is also very challenging, because adequate performance evaluation of such components requires full-wave electromagnetic (EM) simulation, which is computationally expensive. Although high-fidelity EM analysis...
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Urban dew formation efficiency and chemistry in Poland
PublikacjaThe measurements of dew formation efficiency and chemistry were performed in Poland in September 2009, as a part of a longer, two-year sampling campaign. Pairs of sites, representing centers of major Polish cities and rural conditions in three different regions, were compared. With the aim to get more detailed landuse-oriented characteristics of dew, two additional sites were set close to Wroclaw. Collection of dew at each site...
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The KLC Cultures, Tacit Knowledge, and Trust Contribution to Organizational Intelligence Activation
PublikacjaIn this paper, the authors address a new approach to three organizational, functional cultures: knowledge culture, learning culture, and collaboration culture, named together the KLC cultures. Authors claim that the KLC approach in knowledge-driven organizations must be designed and nourished to leverage knowledge and intellectual capital. It is suggested that they are necessary for simultaneous implementation because no one of...
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How do responsible universities perceive their social engagement? In search of signs of Creating Shared Value by the University
PublikacjaObjectives: University social responsibility still lacks legitimisation and is perceived as a burden that hinders academics from doing research and teaching. Creating Shared Value by the University may serve as a tool to motivate universities to engage in initiatives for society, as this is beneficial for both parties. Yet, some researchers perceive the creation of economic value as inappropriate for academia. Thus, it was interesting...
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5G/6G optical fronthaul modeling: cost and energy consumption assessment
PublikacjaIn fifth generation (5G) and the future beyond 5G (6G) radio access networks (RANs), the cost of fronthaul deployment is a main challenge for mobile network operators. Depending on different constraints, there are various solutions to deploy an efficient fronthaul. Fiber-optic-based fronthaul offers long-term support with regard to a rapid increase in capacity demands. When fiber connections, either point-to-point (P2P) or point-to-multipoint...
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Machine-Learning-Based Global Optimization of Microwave Passives with Variable-Fidelity EM Models and Response Features
PublikacjaMaximizing microwave passive component performance demands precise parameter tuning, particularly as modern circuits grow increasingly intricate. Yet, achieving this often requires a comprehensive approach due to their complex geometries and miniaturized structures. However, the computational burden of optimizing these components via full-wave electromagnetic (EM) simulations is substantial. EM analysis remains crucial for circuit...
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Nonlinear Control of a Doubly Fed Generator Supplied by a Current Source Inverter
PublikacjaNowadays, wind turbines based on a doubly fed induction generator (DFIG) are a commonly used solution in the wind industry. The standard converter topology used in these systems is the voltage source inverter (VSI). The use of reverse-blocking insulated gate bipolar transistor (RB-IGBT) in the current source inverter topology (CSI), which is an alternative topology, opens new possibilities of control methods. This paper presents...
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Probabilistic seismic assessment of RC box-girder highway bridges with unequal-height piers subjected to earthquake-induced pounding
PublikacjaThis paper uses the probabilistic seismic assessment to study the effects of pounding and irregularity on the seismic behavior of typical concrete box-girder bridges with four levels of altitudinal irregularity. To extend the results for all bridges in the same class, uncertainty related to the earthquake, structural geometries, and materials are considered. Pounding is likely to take place in two cases: the first one concerns...
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Aspects of intergranular corrosion of AISI 321 stainless steel in high-carbon-containing environments
PublikacjaPurpose – The purpose of this paper is to present a case study of unexpected sensitization to intergranular corrosion of highly resistant AISI 321 steel in petrochemical conditions, where it was subjected to the simultaneous influence of elevated temperature of 250°C and vapors from the asphalt production process. Design/methodology/approach – Corrosion coupons were exposed in an installation carrying asphalt vapors. To identify...
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Ionic Liquid Assisted Dissolution of Dissolved Organic Matter and PAHs from Soil Below the Critical Micelle Concentration
PublikacjaIncreased use and production of ionic liquids (ILs) may result in emissions into the environment. Particularly vulnerable are industrial areas and landfills where ILs are utilized and ultimately disposed of. This study investigates how IL contamination can affect soil properties and the sorption of pre-existing contaminants. The commonly used IL 1-methyl-3-octyl imidazolium chloride ([OMIM][Cl]) was added at various quantities...
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Development of cooperation in localized cooperation networks: A comparative study of cluster organizations and technology parks
PublikacjaThe main aim of the paper is to analyze the level of development of cooperative relationships in localized cooperation networks – among enterprises associated in cluster organizations and park tenants. The author reports the findings from the quantitative study carried out in the selected cluster organizations and technology parks functioning in Poland. The basic method of data collection was a survey questionnaire. The research...
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Assessment of diversity and composition of bacterial community in Sludge Treatment Reed Bed systems
PublikacjaDue to their low emission of odours and lack of the need to apply additional chemical agents, sludge treatment reed beds (STRBs) constitute an economically feasible and eco-friendly approach to sewage sludge management. Correctly designed and operated STRBs ensure effective reduction of the dry matter content coupled with the mineralisation of organic compounds. Successful operation of STRBs relies on complex interactions between...
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CREATIVE PLACEMAKING IN POLAND. CAN ART BECOME AN EFFECTIVE TOOL OF URBAN REGENERATION?!
PublikacjaThe main aim of the paper is to examine the role of creative placemaking in shaping the urban environment in Polish cities. It also focuses on challenges and obstacles that creative placemaking projects encounter in Polish realities. Creative placemaking is a “micro-development” strategy (Johnson 2009) that focuses on cultural participation, com¬munity engagement and highlights the social role of arts and culture. Artistic interventions...
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Computationally-Efficient Statistical Design and Yield Optimization of Resonator-Based Notch Filters Using Feature-Based Surrogates
PublikacjaModern microwave devices are designed to fulfill stringent requirements pertaining to electrical performance, which requires, among others, a meticulous tuning of their geometry parameters. When moving up in frequency, physical dimensions of passive microwave circuits become smaller, making the system performance increasingly susceptible to manufacturing tolerances. In particular, inherent inaccuracy of fabrication processes affect...
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Corrosion Resistance and Surface Bioactivity of Ti6Al4V Alloy after Finish Turning under Ecological Cutting Conditions
PublikacjaThe influence of cooling conditions and surface topography after finish turning of Ti6Al4V titanium alloy on corrosion resistance and surface bioactivity was analyzed. The samples were machined under dry and minimum quantity lubrication (MQL) conditions to obtain different surface roughness. The surface topographies of the processed samples were assessed and measured using an optical profilometer. The produced samples were subjected...
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The Application of Satellite Image Analysis in Oil Spill Detection
PublikacjaIn recent years, there has been an increasing use of satellite sensors to detect and track oil spills. The satellite bands, namely visible, short, medium infrared, and microwave radar bands, are used for this purpose. The use of satellite images is extremely valuable for oil spill analysis. With satellite images, we can identify the source of leakage and assess the extent of potential damage. However, it is not yet clear how to...
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Tolerance-Aware Optimization of Microwave Circuits by Means of Principal Directions and Domain-Restricted Metamodels
PublikacjaPractical microwave design is most often carried out in the nominal sense. Yet, in some cases, performance degradation due to uncertainties may lead to the system failing to meet the prescribed specifications. Reliable uncertainty quantification (UQ) is therefore important yet intricate from numerical standpoint, especially when the circuit at hand is to be evaluated using electromagnetic (EM) simulation tools. Tolerance-aware...
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Rapid Yield Optimization of Miniaturized Microwave Passives by Response Features and Variable-Fidelity EM Simulations
PublikacjaThe operation of high-frequency devices, including microwave passive components, can be impaired by fabrication tolerances but also incomplete knowledge concerning operating conditions (temperature, input power levels) and material parameters (e.g., substrate permittivity). Although the accuracy of manufacturing processes is always limited, the effects of parameter deviations can be accounted for in advance at the design phase...
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Models of using the Internet by young Poles and their social capital.
PublikacjaHighlights • Study examining Polish youth on internet usage styles. • Online communication is the most common form of spending time on the Internet. •...
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Yade-open DEM: an open-source software using a discrete element methodto simulate granular material
PublikacjaPurpose - YADE-OPEN DEM is an open source software based on the Discrete Element Method which uses object oriented programming techniques. The paper describes the softwarearchitecture.Design/methodology/approach - The DEM chosen uses position, orientation, velocity and angular velocity as independent variables of simulated particles which are subject to explicit leapfrog time-integration scheme (Lagrangian method). The three-dimensional...
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Seismic damage diagnosis in adjacent steel and RC MRFs considering pounding effects through improved wavelet-based damage-sensitive feature
PublikacjaThis paper aims to propose complex Morlet (cmorfb-fc) wavelet-based refined damage-sensitive feature (rDSF) as a new and more precise damage indicator to diagnose seismic damages in adjacent steel and Reinforced Concrete (RC) Moment Resisting Frames (MRFs) assuming pounding conditions using acceleration responses. The considered structures include 6- and 9-story steel and 4- and 8-story RC benchmark...
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Oddziaływanie przepięć łączeniowych na izolację kabli polietylenowych
PublikacjaDrzewienie elektryczne jest jedną z form degradacji izolacji w kablach elektroenergetycznych, szczególnie w końcowej fazie rozwoju, jako następstwo drzewienia wodnego. W związku z tym konieczne jest jego wykrywanie w celu poprawnej eksploatacji linii kablowych. Ważna jest przy tym znajomość mechanizmu powstawania i rozwoju w czasie wyładowań niezupełnych (wnz), która może wyznaczyć stan i tempo pogarszania izolacji. W pracy analizowano...
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Techniczne i ekonomiczne aspekty wykorzystania przekształtników dwukierunkowych w praktyce
PublikacjaNowoczesne napędy z silniami indukcyjnymi klatkowymi i przemiennikami częstotliwości stanowią blisko 90% napędów elektrycznych z regulowana prędkością kątową. Dzięki zastosowaniu nowych typów silników, przekładni oraz nowych generacji tranzystorów IGBT w przekształtnikach napędy te są energooszczędne, zaś koszt ich instalacji zwraca się średnio w ciągu kilkudziesięciu miesięcy od chwili zainstalowania. W 95% są to napędy z jednokierunkowym...
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Governmental supported space internship programmes in new ESA member states - Polish perspective
PublikacjaOver last 10 years ve new countries - Czech Republic, Romania, Poland, Hungary and Estonia - have joined the European Space Agency. These countries are currently experiencing a considerable increase of space activities aiming to take part in the European and Global space market. New companies, start-ups and consortiums have been created alongside oces of foreign entities have opened their premises in these countries. All of them...