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Wpływ ukształtowania zbrojenia na zarysowanie i nośność żelbetowego węzła tarczowego ze wspornikiem
PublicationPraca ma charakter eksperymentalno-teoretyczny i dotyczy zagadnień związanych z żelbetowymi tarczami pracującymi w przestrzennym układzie konstrukcji budynków. Celem niniejszej dysertacji było określenie wpływu głównych parametrów jakimi są sposób ukształtowania zbrojenia i smukłość ścinania na zarysowanie i nośność żelbetowego przestrzennego węzła tarczowego ze wspornikiem. Na podstawie aktualnego stanu wiedzy, opracowano program...
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Carbon dioxide sequestration by industrial wastes through mineral carbonation: Current status and perspectives
PublicationMineral carbonation using natural minerals or industrial wastes is a safe and promising strategy for CO2 sequestration. Application of industrial wastes for this purpose has significant ecological and environmental value, which is one of the key green technologies in the global carbon mitigation. This review summarizes the current research status of CO2 mineralization by industrial wastes. This work surveys the mechanisms and capacities...
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Zmodernizowany most Łazienkowski w Warszawie – analizy z wykorzystaniem modelu numerycznego MES
PublicationW artykule przedstawiono proces modelowania statycznego przęseł mostu Łazienkowskiego w Warszawie, który został poddany odbudowie po pożarze 14 lutego 2015 r. Sprawdzające obliczenia numeryczne wykonano w związku z badaniami konstrukcji podczas próbnego obciążenia. Przeprowadzono weryfikację obliczeń projektowych i zaprojektowano próbne obciążenie. Podsumowano wyniki analizy i badań. Dodatkowo opisano nową, stalową konstrukcję...
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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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Central heating temperature control algorithm for systems with condensing boilers
PublicationThe problem of control of a central heating system in a small residence is considered. It is assumed that the system is based on a condensing boiler. Since the boiler efficiency depends on a returning water temperature, the proposed control goal is to provide proper air temperature in the residence as well as the lowest possible water temperature. The proposed algorithm is applied to two buildings. Both of them have the same heating...
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The validation process of truss model with joint eccentricities
PublicationNowadays, due to the technological reasons in modern lightweight steel trusses, fabricated from cold-formed sections, positive eccentricities appear in the truss nodes, to induce additional forces truss chords. In order to account for the real load-carrying capacity of truss node area the steel structure research was conducted in scale 1:1. As a result of experimental research, the forms of deformation and strains of the walls...
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Combined thrust radial bearing of a submarine main shaft – Design and analysis of failure
PublicationThis paper presents an analysis of the combined thrust radial bearing of a submarine propulsion shaft. The lubrication system of the bearing is based on a fixed ring. The efficiency of the lubrication system depends on the shaft speed and temperature, which affects oil viscosity. In turn, the thrust bearing load also depends on the rotational speed of the shaft, because as the speed increases, the drag of the ship increases simultaneously,...
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ECONOMIC MEASURES AGAINST A PANDEMICS
PublicationThe appropriate level of treatment during periods of increasing workload in the health care system or a particular hospital is ensured either by changing the organization of the system and the principles of use of resources such as space, staff and consumables or their redistribution, or by financial resources such resources are increased or replenished. This article contributes to improve the concept of resource allocation as...
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Increasing the lifetime of engineering structures through the use of composite laggings
PublicationThe use of composite laggings prevents concrete (chemical and biological) corrosion. Columns coated with composite or reinforced composite are more resistant to negative environmental impact on concrete or steel. The mechanical properties of the reinforced casing also cause that these types of columns are more resistant to lateral forces. The applied casing limits carbonization of concrete and cyclical freezing and thawing with...
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Experimental test of nonclassicality with arbitrarily low detection efficiency
PublicationWe theoretically introduce and experimentally demonstrate the realization of a nonclassicality test that allows for arbitrarily low detection efficiency without invoking an extra assumption of independence of the devices. Our test and its implementation is set in a prepare-and-measure scenario with an upper limit on the classical communication capacity of the channel through which the systems are communicated. The essence for our...
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Multi-objective Tabu-based Differential Evolution for Teleportation of Smart Virtual Machines in Private Computing Clouds
PublicationWe propose a multi-objective approach for using differential evolution algorithm with tabu search algorithm as an additional mutation for live migration (teleportation) of virtual machines. This issue is crucial in private computing clouds. Teleportation of virtual machines is supposed to be planned to determine Pareto-optimal solutions for several criteria such as workload of the bottleneck host, communication capacity of the...
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Field investigation of low-temperature cracking and stiffness moduli on selected roads with conventional and high modulus asphalt concrete
PublicationHigh Modulus Asphalt Concrete (HMAC) was introduced in Poland as a one of the solutions to the problem of rutting, type of deterioration common in the 1990s. After first encouraging trials in 2002 HMAC was widely used for heavily loaded national roads and motorways. However some concerns were raised about low-temperature cracking of HMAC. This was the main reason of the studies presented in this article were started. The article...
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Iridium 5d -electron driven superconductivity in ThIr3
PublicationA polycrystalline sample of superconducting ThI r 3 was obtained by arc-melting Th and Ir metals. Powder x-ray diffraction revealed that the compound crystalizes in a rhombohedral crystal structure (R-3m, s.g. #166) with the lattice parameters: a = 5.3394 ( 1 ) Å and c = 26.4228 ( 8 ) Å . Normal and superconducting states were studied by magnetic susceptibility, electrical resistivity, and heat capacity measurements. The results...
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Tuning the Laser-Induced Processing of 3D Porous Graphenic Nanostructures by Boron-Doped Diamond Particles for Flexible Microsupercapacitors
PublicationCarbon (sp3)-on-carbon (sp2) materials have the potential to revolutionize fields such as energy storage and microelectronics. However, the rational engineering and printing of carbon-on-carbon materials on flexible substrates remains a challenge in wearable electronics technology. This study demon-strates the scalable fabrication of flexible laser-induced graphene (LIG)-boron doped diamond nanowall (BDNW) hybrid nanostructures...
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The Impact of Direct Normal Irradiation on the Solar Tower Power Plant Performance based on Real and Satellite Data: Analysis on Algerian Regions
PublicationThe present paper presents a deep study on the possibility of implementing Concentrated Solar Power (CSP) plants in Algeria for the production of the electrical energy. Indeed, this paper focusses mainly on the main parameters, which can have an important impact on the choice of the location, the dimension and the available thermal energy storage system. In this study, three main parameters are investigate...
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Tailoring of SiOC composition as a way to better performing anodes for Li-ion batteries
PublicationPolymer derived silicon oxycarbide (SiOC) ceramics are investigated as potential anodes for lithiumion batteries. Different SiOC ceramics are prepared by pyrolysis (1000 °C and 1400 °C under controlled argon atmosphere) of polysiloxanes ceramic precursors. Preceramic polymers are synthesized using the sol–gel method. Phenyltriethoxysilane (PhTES) and methyltriethoxysilane (MTES) have been used as starting precursors and mixed with...
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Water-Lubricated Sintered Bronze Journal Bearings—Theoretical and Experimental Research
PublicationWater lubricated bearings are used from many years in shipbuilding, hydro power and other industries because of their advantages such as: extensive serviceable life, low coefficient of friction, longevity of shaft sleeve, good abrasion resistance, low maintenance required, unit simplicity, no danger of pollution and low price. Various types of water lubricated sliding bearings have been tested at the Technical University of Gdansk...
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Encapsulation of an anticancer drug Isatin inside a host nano-vehicle SWCNT: a molecular dynamics simulation
PublicationThe use of carbon nanotubes as anticancer drug delivery cargo systems is a promising modality as they are able to perforate cellular membranes and transport the carried therapeutic molecules into the cellular components. Our work describes the encapsulation process of a common anticancer drug, Isatin (1H-indole-2,3-dione) as a guest molecule, in a capped single-walled carbon nanotube (SWCNT) host with chirality of (10,10). The...
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Improving the Performance of a Graphite Foil/Polyaniline Electrode Material by a Thin PEDOT:PSS Layer for Application in Flexible, High Power Supercapacitors
PublicationIn this study, we present a novel strategy for enhancing polyaniline stability and thus obtaining an electrode material with practical application in supercapacitors. A promising (graphite foil/polyaniline/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) GF/PANI/PEDOT:PSS) electrode material was characterized and used in the construction of a symmetric supercapacitor that provides an outstanding high power density. For this...
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Multifaceted Analyses of Four Different Prototype Lightweight Photovoltaic Modules of Novel Structure
PublicationDynamic growth of photovoltaic capacity in Poland encourages many entities to invest in photovoltaic systems. However, in the case of buildings with low roof-bearing capacity it can be problematic or even impossible to mount conventional PV modules due to their relatively high weight. Hence, the use of lightweight PV modules is a potential solution. In this paper four different prototype silicon lightweight modules of novel structure...
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Projektowanie zbiornika na nieczystości ciekłe
PublicationW artykule przedstawiono proces projektowania zbiornika podziemnego na nieczystości ciekłe o pojemności ok. 10 m3 posadowionego na gruntach niespoistych (sypkich). Porównano wartości sił wewnętrznych w przypadku skrajnie różnych warunków gruntowych: piasku drobnego o ID = 0,2 oraz żwiru o I D = 0,7. Dodatkowo przeanalizowano wpływ modelu obliczeniowego podłoża na wyniki sił wewnętrznych. Opisano procedurę normową pozwalającą na...
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Direct design of Controlled Modulus Columns (CMC) based on in-situ testing
PublicationIn this paper, the serviceability limit state and bearing capacity of tension screw displacement piles were analyzed using the results of static pile load tests, carried out on the test plot near the Elbląg city, and field, and laboratory tests. The paper presents the methodology of determining the pile load-settlement curve using different types of t-z transfer functions. The new method of constructing the pile load-settlement...
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Functional Safety and Cybersecurity Analysis and Management in Smart Manufacturing Systems
PublicationThis chapter addresses some of the issues of the integrated functional safety and cybersecurity analysis and management with regard to selected references and the functional safety standards: IEC 61508, IEC 61511, ISO 13849-1 and IEC 62061, and a cybersecurity standard IEC 62443 that concerns the industrial automation and control systems. The objective is to mitigate the vulnerability of industrial systems that include the information...
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Lossless Compression of Binary Trees with Correlated Vertex Names
PublicationCompression schemes for advanced data structures have become the challenge of today. Information theory has traditionally dealt with conventional data such as text, image, or video. In contrast, most data available today is multitype and context-dependent. To meet this challenge, we have recently initiated a systematic study of advanced data structures such as unlabeled graphs [1]. In this paper, we continue this program by considering...
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The Finite Elements Method application to assesment the impact of turbulence generated by wind turbines on their lacation inclose proximity of overhead high voltage power transmissionlines
PublicationThe paper presents selected aspects of construction of wind turbines location concerning aerodynamic impact on power lines. Reaserch is based on the source data concerning the aerodynamic impact of a wind farm consisting of 8 turbines and 400 kV power line, an analysis of the possibility of wind farm locating in the immediate vicinity of the line was carried out. There are serious problems with locating higher capacity wind farms...
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Numerical modelling and experimental verification of compressible squeeze film pressure
PublicationThe validity of using the Reynolds equation for compressible squeeze film pressure was tested with computational fluid dynamics (CFD). A squeeze film air bearing was instrumented with pressure sensors and non-contacting displacement probes to provide transient measurements of film thickness and pressure. The film thickness measurements also provided input parameters to the numerical prediction. However, numerical results showed...
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Design analysis of Tesla micro-turbine operating on a low-boiling medium
PublicationThis paper presents results of the design analysis of a Tesla bladeless turbine intended for a co-generating micro-power plantof heat capacity 20 kW, which operates in an organic Rankine cycle on a low-boiling medium. Numerical calculations of flowin several Tesla turbine models were performed for a range of design parameters. Results of investigations exhibit interestingfeatures in the distribution of flow parameters within the...
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Influence of nodes with positive eccentricity on load-carrying capasity of truss' top chords in trusses made of welded cold-formed members.
PublicationIn order to establish the influence of eccentric crossing of truss members on the load-carrying capacity of the folded chord of a hat-section truss, a research model was created and preliminary numerical analysis of the truss was performed with the use of Marc Mentat programme. Distorial instability of crossheads caused by deviation of loose (unmounted) channel section web’s bends was observed. Due to the slenderness of the section’s...
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Alternative Modeling of Volunteer Based Systems
PublicationThe canonical approach to model a flow of a voluntary based computing, as presented in Chapter 7 may tax the capacity of the simulator, especially when a more complex model of Voluntary Computing, proposed in [1], is used which would imply that, for typical heterogeneous groups of volunteers, several thousands of threads would have to be run inside the simulator, to mimic closely the behaviour of every volunteer. This chapter presents...
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Nonlinear FEM 2D failure onset prediction of composite shells based on 6-parameter shell theory
PublicationWithin the framework of the nonlinear 6-parameter shell theory with the drilling rotation and asymmetric stress measures, the modifications of Tsai-Wu and Hashin laminate failure initiation criteria are proposed. These improvements enable to perform first ply failure estimations taking into account the non-symmetric stress measures. In order to check the validity of the proposed criteria, finite element analyses are performed with...
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WIKI-WS as a C2 NIWA Web Service Management Platform
PublicationThe Wiki-WS platform was implemented within the C2 NIWA project for production purposes. Wiki-WS stands for developing, managing and maintaining web services. The production deployment needed implementation of several functional improvements and establishing a strong security 7 safety policy. The WikiWS platform has to be used as an educational environmement for developing web sevices and production environment for execution of...
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Optimization of Nuclear Power Share in the Structure of Electricity Production in Poland in Time Perspective by 2060
PublicationThe author of this paper presented the results of a system analysis using MARKAL model, aiming at the optimization of nuclear power share in power generation structure in Poland in time perspective by 2060. Optimization criterion is the minimization of the objective function, i.e. the total cost of energy system, taking into account constraints related to CO2, SOx and NOx emissions and obligatory shares of electricity from renewable...
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Search for the most useful geometry of an acoustic journal bearing
PublicationComputer simulations of a number of journal bearing’s geometries utilising acoustic levitation were carried out. The choice of the best geometry depended on the ability of a deformed shape, created by piezo-electric elements, to facilitate squeeze film ultrasonic levitation, and also to create three evenly distributed diverging aerodynamic gaps. Deformations of analysed variants of the bearing’s shape were generated by numerical...
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Application of wavelength division multiplexing in sensor networks
PublicationOver the past few years the need to acquire data on various parameters from a number of sensors grew. The need that led to the development of a network of sensors which enables simultaneous control and measurement in a wide range of applications. The aim of this article is to discuss a possibility of connecting a variety of sensors in a network that would utilize WDM technology. Wavelength Division Multiplexing is commonly used...
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Superconductivity in the Endohedral Ga Cluster Compound PdGa5
PublicationSuperconductivity is observed below Tc = 1.6 K in an endohedral Ga cluster compound PdGa5 using magnetization and heat capacity measurements. Electronic structure calculations show that the density of states (DOS) at the Fermi level is dominated by Ga s and p states and that the overall shape of DOS is similar to what was found in other endohedral Ga cluster superconductors, such as MoxGa5x+1, ReGa5, and T2Ga9 (T = Rh and Ir)....
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A Review of Reduction Methods of Impact of Common-Mode Voltage on Electric Drives.
PublicationIn this survey paper, typical solutions that focus on the reduction in negative effects resulting from the common-mode voltage influence in AC motor drive applications are re-examined. The critical effectiveness evaluation of the considered methods is based on experimental results of tests performed in a laboratory setup with an induction machine fed by an inverter. The capacity of a common-mode voltage level reduction and voltage...
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Parametry mechaniczne platformy roboczej na podstawie badań DMT
PublicationNośność platformy roboczej określana jest w sposób analogiczny do nośności podłoża uwarstwionego, w którym warstwa wierzchnia zbudowana z gruntu niespoistego spoczywa na słabonośnym podłożu z gruntu spoistego. Badanie DMT wykorzystano do wyznaczenia parametrów wytrzymałościowych podłoża (kąta tarcia wewnętrznego warstwy górnej i wytrzymałości na ścinanie bez odpływu podłoża słabonośnego) oraz do wyznaczenia modułu odkształcenia...
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Failure of cold-formed beam: How does residual stress affect stability?
PublicationIn machine industry, stresses are often calculated using simple linear FEM analysis. Occasional failures of elements designed in such a way require recomputation by means of more sophisticated methods, eg. including plasticity and non-linear effects. It usually leads to investigation of failure causes and improvement of an element in order to prevent its unwanted behavior in the future. The study presents the case where both linear...
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The effect of laser on metal surfaces for multidisciplinary usage in material and thermal engineering
PublicationThe subject of heat transfer and cooling systems is still a matter of contention in many different fields of science and industry. Infrigidation is much more difficult than warming, and so, much more needed in more and more different devices, starting from massive industrial machinery and air conditioning in commercial buildings, up to micro and nano-surgery tools. In fact, the size of many cooling systems is still a problem. It...
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Wireless Charging Station Design for Electric Scooters: Case Study Analysis
PublicationThis study proposes an example of a wireless charging station design for a small-scale vehicle available on the market. The article analyzes basic transmitter inverter topologies and their compensation methods in terms of flexibility of control, tolerance to uncertainty in positioning, and the possibility of decreasing the integration price. Our comprehensive analysis focuses on the battery voltage range, energy capacity, cost,...
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Normal stress distribution in built‑up cold‑formed column in relation to interconnecting bolt spacing
PublicationIn order to increase a stiffness of cold-formed steel (CFS) elements it is practised to built-up the cross-section. In the analysed case, a main element is strengthened by adding extra chord in contact partially along the column. This additional chord acts as a longitudinal stiffener connected with the main section by series of bolts. Authors check whether rules applied over the years, for hot-rolled elements, can be indiscriminately...
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Modelowanie kratownicy z kształtowników giętych na zimno z mimośrodami dodatnimi w węźle = Modelling of truss with cold-formed section and positive eccentricyty in the node.
PublicationThe topic of this research is establishing load-carrying capacity of compressed and tensed chords of trusses made of cold-formed open cross-sections. Occurrence of bending in the truss’ chord is the result of specific production technology assumed by the designer and producer of lattice girder’s systems. The aim of this research is to present methodology of conduct while creating numerical models that best depict the behaviour...
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Large thermo-elastic displacement and stability FEM analysis of multilayered plates and shells
PublicationThe paper concerns the load capacity analysis of thermally loaded multilayered plates and shells. The multilayered body is treated as an equivalent single layer whose kinematics is consistent with first order shear deformation theory. The authors focus on the thermo-elastic stability problem of the thin-walled structures. The equilibrium paths are traced with the use of Riks-Wempner-Ramm algorithm. By making use of the Tsai-Wu...
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Experimental study of the post tensioned prestressed concrete corbels
PublicationThe results of experimental investigation of 6 symmetrical double prestressed corbels of variable shear span to depth ratio and variable location of prestressing bars are presented in the paper. The post ten- sioned corbels were prestressed with Macalloy 1030 bars of 25 mm in diameter. The results of the tests were compared with the cracking and load carrying capacity of corbels reinforced with passive reinforce- ment. As a result...
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Superconductivity in the niobium-rich compound Nb5Se4
PublicationThe niobium rich selenide compound Nb5Se4 was synthesized at ambient pressure by high-temperature solid–state reaction in a sealed Ta tube. Resistivity and heat capacity measurements reveal that this compound is superconducting, with a Tc = 1.85K. The electronic contribution to the specific heat γ and the Debye temperature are found to be 18.1 mJmol−1K−2 and 298 K respectively. The calculated electron-phonon coupling constant λep...
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Efficiency of the Use of LTE System Radio Resources in Highway Transport Enironment
PublicationThe paper describes the problem of analysis of throughput-coverage characteristics of the LTE system. Simulation results of the efficiency of the use of LTE radio resources are presented. Simulation studies on the basis of original model of the LTE network simulator were carried out. In addition, the evaluation of throughput for a single connection, and available capacity were evaluated in the context of the use of the same...
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Methods of Network Resource Provisioning for the Future Internet IIP Initiative
PublicationIn this paper, we present specification, design and implementation aspects of a network resource provisioning module introduced for the Polish Initiative of Future Internet called System IIP. In particular, we propose a set of novel LP optimization models of network resource provisioning designed to minimize the network resource consumption, either bandwidth or node’s computational power, as well as to maximize the residual capacity....
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Modeling of truss with cold-formed section and positive eccentricity in the node
PublicationThis work is dedicated to establishing the load carrying capacity of tensed and compressed truss’ nodes made of cold-formed open cross sections. The occurrence of bending in the truss’ nodes is the result of a specific production technology for system lattice girders assumed by the designer and the producer. The aim of this research is to present the methodology of conduct for creation of computational models that best depict the...
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Higher harmonics produced by traction substations – computer modelling and experimental verification
PublicationVoltage and current harmonics have a detrimental effect on the components of a power system. Current harmonics may result in the overload and damage to power transformers, although the rms value of load current does not exceed their current-carrying capacity. Voltage harmonics may result in, for example, damage to capacitor banks used to compensate reactive power. Devices which contribute to both current and voltage distortion...
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Research on Quality Requirements of Data Transmission Services in RSMAD
PublicationThe paper presents a results and analysis of research of the quality of service requirements (defined by the QoS attributes) for imaging data transmission services using Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short RSMAD). The paper also presents and discusses results of test on the impact of the size of photos from traffic enforcement cameras on the average transmission time. These...