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Lax-Wendroff and McCormack Schemes for Numerical Simulation of Unsteady Gradually and Rapidly Varied Open Channel Flow
PublicationTwo explicit schemes of the finite difference method are presented and analyzed in the paper. The applicability of the Lax-Wendroff and McCormack schemes for modeling unsteady rapidly and gradually varied open channel flow is investigated. For simulation of the transcritical flow the original and improved McCormack scheme is used. The schemes are used for numerical solution of one dimensional Saint-Venant equations describing free...
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Wideband crossover structure with double ring resonators
PublicationThe structure of a four-port microstrip crossover is presented. The device is composed of two ring resonators, one circular and one built from meander lines, connected by four straight lines. The equivalent circuit model of the crossover is derived. The structure is designed on thin and flexible substrate to allow it to bend. The possibility of applying the device on curved surfaces is tested experimentally.
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Wpływ odnawialnych źródeł generacji energii na bezpieczeństwo pracy krajowego systemu elektroenergetycznego
PublicationW referacie omówiono ogólne problemy związane z rozwojem systemów elektroenergetycznych, w tym związane z tzw. źródłami energii odnawialnej (OZE). Na tym tle przedstawiono zagadnienia związane z bezpieczeństwem energetycznym, wpływem OZE na bezpieczeństwo i dalej zagadnienia związane z kierunkami rozwoju systemów elektroenergetycznych.
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The Methods for RTS Noise Identification
PublicationIn the paper authors present two methods, which allows to identify the RTS noise in noise signal of semiconductor devices. The first one was elaborated to identify the RTS noise and also to estimate the number of its levels. The second one can be used to estimate all of the parameters of Gaussian and non-Gaussian components in the noise signal in a frequency domain.
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An Algorithm for Optimizing the Determination of Cycling Routes on the Example of the Gdansk Agglomeration
PublicationPhysical activity is an essential part of a healthy lifestyle. One of the manifestations of the change in a society type from consumer to information one is the understanding of the importance of ecology and a healthy lifestyle. This is evident, inter alia, in the inventiveness and involvement of the society in the start-up and solutions referred to as the Smart City. One example is the development of e-bike rental and local investments...
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Metodyka badawcza z wykorzystaniem wskaźnika całkowitej efektywności wyposażenia
PublicationW opracowaniu przedstawiono metodykę oceny tzw. wskaźnika całkowitej efektywności wyposażenia (OEE). W pierwszej części omówiono wskaźnik OEE i jego budowę oraz zaprezentowano ogólny schemat postępowania w celu obliczenia jego wartości, natomiast dalsza część pracy zawiera studium przypadku. Szczególnym aspektem przeprowadzonej analizy był charakter zakładu produkcyjnego, ponieważ dotyczył on produkcji małoseryjnej oraz wytwarzania...
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Regularized identification of fast time-varying systems - comparison of two regularization strategies
PublicationThe problem of identification of a time-varying FIR system is considered and solved using the local basis function approach. It is shown that the estimation (tracking) results can be improved by means of regularization. Two variants of regularization are proposed and compared: the classical L2 (ridge) regularization and a new, reweighted L2 one. It is shown that the new approach can outperform the classical one and is computationally...
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Human Computer Interface for Tracking Eye Movements Improves Assessment and Diagnosis of Patients With Acquired Brain Injuries
PublicationOne of the first clinical signs differentiating the minimally conscious state from the vegetative state is the presence of smooth pursuit eye movements occurring in direct response to moving salient stimuli. Glasgow Coma Scale (GCS) is one of the most commonly used diagnostic tools for acute phase assessment of the level of consciousness, together with a neurological examination. These classic measures are limited to qualitative...
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Weather Hazard Avoidance in Modeling Safety of Motor-Driven Ship for Multicriteria Weather Routing
PublicationWeather routing methods find the most suitable ocean?s route for a vessel, taking into account changeable weather conditions and navigational constraints. In the multicriteria approach based on the evolutionary SPEA algorithm one is able to consider a few constrained criteria simultaneously. The approach applied for a ship with hybrid propulsions has already been presented by one of the authors on previous TransNav?2009. This time...
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Akaike's final prediction error criterion revisited
PublicationWhen local identification of a nonstationary ARX system is carried out, two important decisions must be taken. First, one should decide upon the number of estimated parameters, i.e., on the model order. Second, one should choose the appropriate estimation bandwidth, related to the (effective) number of input-output data samples that will be used for identification/ tracking purposes. Failure to make the right decisions results...
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La sfida di "Re Cotone". Una nuova storia del capitalismo attraverso la storia delle commodities?
PublicationThe article is divided into two parts. In the first one, it highlights the role of commodities in real economy and it observes the coincidence of their price increase after 2003 and their importance as a research topic particularly in the framework of global history. In the second one, it propose a comparative analysis of two recent books on cotton, considering similarities and differences of their approaches, and the difficult...
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Synthesis and crystal structure of ferrocenyl benzothiazole derivatives
PublicationNovel ferrocenyl-containing benzothiazole derivatives were synthesised in moderate yields by one-pot α-amidoalkylation of ferrocene. The reaction conditions were critically evaluated and the crystal structure of one of the amidoalkylated ferrocenes was resolved. Oxidation of the obtained compounds led to known fully aromatic 2-ferrocenylbenzothiazole in 81 % yield, which represents a convenient alternative to earlier methods utilizing...
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Examining Statistical Methods in Forecasting Financial Energy of Households in Poland and Taiwan
PublicationThis paper examines the usefulness of statistical methods in forecasting the financial energy of households. The study’s objective is to create the innovative ratios that combine both financial and demographic information of households and implement them in the forecasting models. To conduct this objective, six forecasting models are developed using three different methods—discriminant analysis, logit analysis, and decision trees...
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Linear and nonlinear impedance in iron oxide glasses containing alkaline ions and alkali free
PublicationThe linear and nonlinear impedance spectra of oxide glasses were measured in the frequency range of 1 mHz to 1 MHz and in the temperature range of 153K to 483K. Two groups of iron oxide glass samples were prepared, the first one containing alkaline ions and the second one without alkali. In the first group, compositions of glasses were as follows: (in %mol) 50% SiO2 , 25% PbO, 15% Fe2O3 and 15% one of alkaline oxides: Na2O, K2O,...
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Efficient bounds on quantum-communication rates via their reduced variants
PublicationWe investigate one-way communication scenarios where Bob operating on his component can transfer some subsystem to the environment. We define reduced versions of quantum-communication rates and, further, prove upper bounds on a one-way quantum secret key, distillable entanglement, and quantum-channel capacity by means of their reduced versions. It is shown that in some cases they drastically improve their estimation.
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Conjectured strong complementary-correlations tradeoff
PublicationWe conjecture uncertainty relations that restrict correlations between the results of measurements performed by two separate parties on a shared quantum state. The first uncertainty relation bounds the sum of two mutual informations when one party measures a single observable and the other party measures one of two observables. The uncertainty relation does not follow from the Maassen-Uffink uncertainty relation and is much stronger...
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Selection of Organic Coating Systems for Corrosion Protection of Industrial Equipment
PublicationThe most important element of corrosion protection in industrial conditions is the protective coating system. However, selecting the right coating can often be a real problem due to the sheer number of coating manufacturers and their products on the market. A quantitative approach based on the data mining technique used to analyze the obtained multi-site exposure data has been proposed. This was demonstrated by the example of the...
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Influence of bitumen type on cracking resistance of asphalt mixtures used in pavement overlays
PublicationCracking is one of the predominant distresses occurring in flexible pavements, especially in old pavements that were rehabilitated with an asphalt overlay. In such cases asphalt mixtures should be designed to ensure high resistance to reflective cracking because new asphalt layers are exposed to existing cracks of the old pavement. The nature of these cracks can be various (transverse, longitudinal as well as crazy cracking). One...
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Flexomagnetic response of buckled piezomagnetic composite nanoplates
PublicationIn this paper, the equation governing the buckling of a magnetic composite plate under the influence of an in-plane one-dimensional magnetic field, assuming the concept of flexomagnetic and considering the resulting flexural force and moment, is investigated for the first time by different analytical boundary conditions. To determine the equation governing the stability of the plate, the nonlocal strain gradient theory has been...
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Relativity of arithmetic as a fundamental symmetry of physics
PublicationArithmetic operations can be defined in various ways, even if one assumes commutativity and associativity of addition and multiplication, and distributivity of multiplication with respect to addition. In consequence, whenever one encounters ‘plus’ or ‘times’ one has certain freedom of interpreting this operation. This leads to some freedom in definitions of derivatives, integrals and, thus, practically all equations occurring in...
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Logical Interface for Soft Handover – an effective scheme of handovers in Proxy Mobile IPv6
PublicationMultimedia services are currently commonly available on mobile devices. Due to networks' convergence and migration to all-IP networks, mobility management at network layer is required. Moreover, nowadays it is popular to equip mobile devices with more than one wireless interface. Thus, soft handovers can be implemented, which means that an existing connection is removed after a new one is established. Usage of the Logical Interfaces...
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Produkcja energii w Unii Europejskiej przy wykorzystaniu biomasy stałej i odpadów komunalnych
PublicationOmówiono wykorzystanie biomasy stałej i odpadów komunalnych do produkcji energii w Unii Europejskiej (UE-25). Przedstawiono ogólny stopień wykorzystania różnych rodzajów energii odnawialnej. Dość szczegółowo omówiono wykorzystanie biomasy stałej oraz odpadów komunalnych jako nośników energii odnawialnej w poszczególnych krajach UE. Biomasa stała i odpady komunalne stanowią największy udział w strukturze produkcji energii przy...
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New approach for determining the QoS of MP3-coded voice signals in IP networks
PublicationPresent-day IP transport platforms being what they are, it will never be possible to rule out conflicts between the available services. The logical consequence of this assertion is the inevitable conclusion that the quality of service (QoS) must always be quantifiable no matter what. This paper focuses on one method to determine QoS. It defines an innovative, simple model that can evaluate the QoS of MP3-coded voice data transported...
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A simple test for quantum channel capacity
PublicationBased on state and channel isomorphism we point out that semidefiniteprogramming can be used as a quick test for nonzero one-way quantum channelcapacity. This can be achieved by searching for symmetric extensions of statesisomorphic to a given quantum channel. With this method we provide examplesof quantum channels that can lead to high entanglement transmission but stillhave zero one-way capacity, in particular, regions of symmetric...
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Probabilistic sensitivity of limit states of structures. The Monte Carlo simulation
PublicationDesign sensitivity deals with the variation of structural response, implicitly dependent on the design variables of the problem. An attempt is made to implement probabilistic notation in engineering sensitivity analysis. The procedure to implement the sensitivity of a structural limit state to a given basic variable is described in the paper - its main idea, depicted by a flowchart and numerical examples of engineering analysis....
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Reactions of cobalt(ii) chloride and cobalt(ii) acetate with hemisalen-type ligands: ligand transformation, oxidation of cobalt and complex formation. Preliminary study on the cytotoxicity of Co(ii) and Co(iii) hemisalen complexes
PublicationSeveral molecular cobalt(II) complexes, one Co(II) coordination polymer, and one ionic cobalt(III) complex with imine hemisalen ligands were synthesized. The hemisalen ligands were synthesized from o-vanillin (oVP) and diverse aminopyridines (compounds HL1–HL4) or aminophenol (compound HL5). It was observed that cobalt(II) chloride in dry acetonitrile catalyzes a transformation of HL1 and HL3 instead of complex formation. The conversion...
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Crystallization of space: Space-time fractals from fractal arithmetic
PublicationFractals such as the Cantor set can be equipped with intrinsic arithmetic operations (addition, subtraction, multiplication, division) that map the fractal into itself. The arithmetics allows one to define calculus and algebra intrinsic to the fractal in question, and one can formulate classical and quantum physics within the fractal set. In particular, fractals in space-time can be generated by means of homogeneous spaces associated...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublicationThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublicationThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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Super capacitor energy bank MEDCOM UCER-01 in Gdynia trolleybus system
PublicationSince 2001, trolleybus system in Gdynia has been involved in many activities related to the reduction of power consumption, both in terms of implementation and research and development. The installation of the supercapacity energy bank on substation Wielkopolska in 2014 year was one of them. It is the first such big stationary supercapacitor storage system installed in trolleybus supply system in the Middle - Eastern Europe. The...
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The International Mercury Cartel, 1928–1954: Controlling Global Supply
PublicationThis article describes the features of the international mercury marketduringthe firsthalfofthetwentiethcentury.Itanalyzes the various market agreements made, their effectiveness, and their consequences. The period studied is little understood, although it was one in which mercury production greatly increased. It was also one that saw persistent efforts at market manipulation, owing to a series of agreements between Spanish and...
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Influence of thermal effects on mechanical properties of PVDF-coated fabric
PublicationThis paper describes the method of laboratory tests necessary for identification of temperature influence on mechanical properties of polyvinylidene fluoride-coated polyester fabric often used for tensile structures. Two nonlinear model descriptions are investigated. The first one is based on the piece-wise linear relations between stress and strain and the second one on the Murnaghan model of solid behavior. This paper is proposed...
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Multifrequency self-optimizing narrowband interference canceller
PublicationThe problem of cancellation of a nonstationary sinusoidal interference, acting at the output of a linear stable plant, is considered. It is assumed that disturbance is a multifrequency narrowband signal, and that system output is contaminated with wideband noise. It is not assumed that the reference signal is available. Two disturbance cancelling schemes are proposed, one for disturbances with unrelated frequency components, and...
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Intensification of thermal convection near electric devices using flat screens – computer modelling
PublicationIntensification of natural thermal convection near electric devices is possible by application of additional elements as screens creating convection canals close to the device. In the earlier authors paper the results of the analysis of thermal convection with the use of only one additional screen close to the electric device were presented. This paper presents computer modelling of thermal convection when two screens near the...
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Electrohydrodynamic secondary flow in the electrostatic precipitator with spiked electrodes
PublicationIn this work, the results of electrohydrodynamic (EHD) secondary flow measurements in an electrostatic precipitator (ESP) with one-sidedspike electrodes are presented. The EHD secondary flow was measured for one-sided spike electrodes with the spike tips directed either upstream or downstream the primary flow. The results showed different flow patterns for different spike tips direction in respect to the primary flow direction....
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Surface sliding in human abdominal wall numerical models: Comparison of single-surface and multi-surface composites
PublicationDetermining mechanical properties of abdominal soft tissues requires a coupled experimental-numerical study, but first an appropriate numerical model needs to be built. Precise modeling of human abdominal wall mechanics is difficult because of its complicated multi-layer composition and large variation between specimens. There are several approaches concerning simplification of numerical models, but it is unclear how far one could...
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DETECTION OF BREATHING AND HEART RATE USING AN ECG SIGNAL MEASURED WHILE BATHING IN THE BATHTUB
PublicationNowadays a new area of interest is gaining importance - it is home biomedical examination. Intelligent home can be supported by set of devices for habitants observation. It can be particularly useful for elders or person with some health risks but living alone. One of critical locations within the house is bathroom. One of utilities in the bathroom is a bathtub which is sometimes preferred over shower. There are reports of problems...
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Numerical Investigation of Nuclear Reactor Kinetic and Heat Transfer Fractional Model with Temperature Feedback
PublicationAbstract—In the paper, the numerical results concerning the kinetics and proposed heat exchange models in nuclear reactor based on fractional calculus are presented for typical inputs. Two fractional models are proposed and compared with the model based on ordinary derivative. The first fractional model is based on one of the generalized Cattaneo equations. The second one is based on replacing the ordinary to fractional order of...
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Detection of impulsive disturbances in archive audio signals
PublicationIn this paper the problem of detection of impulsive disturbances in archive audio signals is considered. It is shown that semi-causal/noncausal solutions based on joint evaluation of signal prediction errors and leave-one-out signal interpolation errors, allow one to noticeably improve detection results compared to the prediction-only based solutions. The proposed approaches are evaluated on a set of clean audio signals contaminated...
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Azo and azoxythiacrown ethers: synthesis and properties
PublicationA series of 16- and 18-membered azo- and azoxythiacrown ethers have been synthesized by reductive macrocyclization of the respective bis(nitrophenoxy)oxaalkanes. The aromatic residues located in the polyether region of the molecule were introduced to macrocyclic skeletons and their affinities toward different groups of metal cations in ion-selective electrodes were described. X-ray structures for one dinitropodand and one azoxybenzothiacrown...
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On cooperative image denoising
PublicationIn this paper we suggest how several competing image denoising algorithms, differing in design parameters, or even in design principles, can be combined together to yield a better and more reliable denoising algorithm. The proposed fusion mechanism allows one to combine practically all kinds of noise reduction tools. It also allows one to account for the distribution of measurement noise, and in particular - to cope with heavy-tailed...
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Soft-decision schemes for radar estimation of elevation at low grazing angles
PublicationIn modern radars, the problem of estimating elevation angle at low grazing angles is typically solved using superresolution techniques. These techniques often require one to provide an estimate of the number of waveforms impinging the array, which one can accomplish using model selection techniques. In this paper, we investigate the performance of an alternative approach, based on the Bayesian-like model averaging. The Bayesian...
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Concept of a swirling diffuser in batch blending tanks
PublicationThe mixing of two or more components belongs to the category of the most common unit operations, both in technology and in nature. One particular version is homogenization (blending), the effectivity of which is strongly related to the blending time. Among many differentiated individual solutions of mixing systems used in blenders, one should distinguish the class of agitators with diffusers. An analysis of the character of the...
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Relicts of the 16th-century cellar by the St Mary's Church in Gdansk / Relikty piwnicy z XVI w. przy kościele Wniebowzięcia NMP w Gdańsku
PublicationSaint Mary’s church in Gdańsk, one of the largest brick Gothic temples in the World, has got no external chapels – except the House of Councils. Its architectural form, however, is not the result of implementation of one project, but realization of a few transforming concepts. The discovery of the relicts of the 16 th century cellars, located in the corner of the transept and the northern aisle, gives an idea of the process...
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Deflated Preconditioned Solvers for Parametrized Local Model Order Reduction
PublicationOne of steps in the design of microwave filters is numerical tuning using full-wave simulators. Typically, it is a time-consuming process as it uses advanced computational methods, e.g. the finite-element method (FEM) and it usually requires multiple optimization steps before the specification goals are met. FEM involves solving a large sparse system of equations at many frequency points and therefore its computational cost is...
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Classification and fingerprinting of kiwi and pomelo fruits by multivariate analysis of chromatographic and spectroscopic data
PublicationThe fingerprinting capacity of two analytical techniques, HPLC and UV-Vis spectroscopy in the case of fruits samples (kiwi and pomelo) has been investigated. The multivariate exploratory techniques were used for sample discrimination according to the fruit species and subspecies. The combination of principal component analysis with linear discriminant analysis is opening new directions in the fingerprinting analysis. The classifications...
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Improved magnitude estimation of complex numbers using alpha max and beta min algorithm
PublicationThe paper presents an improved algorithm for calculating the magnitude of complex numbers. This problem, which is a special case of square rooting, occurs for example, in FFT processors and complex FIR filters. The proposed method of magnitude calculation makes use of the modified alpha max and beta min algorithm. The improved version of the algorithm allows to control the maximum magnitude approximation error by using an adequate...
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Squashed entanglement for multipartite states and entanglement measures based on the mixed convex roof
PublicationNew measures of multipartite entanglement are constructedbased on two definitions of multipartite information anddifferent methods of optimizing over extensions of the states. Oneis a generalization of the squashed entanglement where one takesthe mutual information of parties conditioned on the state's extensionand takes the infimum over such extensions. Additivity ofthe multipartite squashed entanglement is proved for both versionsof...
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Application of the fluid–structure interaction technique for the analysis of hydrodynamic lubrication problems.
PublicationFluid–structure interaction technique seems to be one of the most promising possibilities for theoretical analysis of lubrication problems. It allows coupling of different physical fields in one computational task, taking into account the interaction between them. In this article, two sets of fluid–structure interaction analyses focusing on the bearing performance evaluation are presented. One analysis was applied to a water-lubricated...
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A High-Arctic flow-through lake system hydrochemical changes: Revvatnet, southwestern Svalbard (years 2010–2018)
PublicationLake ecosystems are strongly coupled to features of their surrounding landscapes such as geomorphology, lithology, vegetation and hydrological characteristics. In the 2010–2018 summer seasons, we investigated an Arctic flow-through lake system Revvatnet, located in the vicinity of the coastal zone of Hornsund fjord in Svalbard, characterising its hydrological properties and the chemical composition of its waters. The lake system...