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On description of periodic magnetosonic perturbations in a quasi-isentropic plasma with mechanical and thermal losses and electrical resistivity
PublicationMagnetosonic periodic perturbations in a uniform and infinite plasma model are considered. Damping due to compressional viscosity, electrical resistivity, and thermal conduction are taken into account, as well as some heating–cooling function, which may destroy the isentropicity of wave perturbations. The wave vector forms arbitrary angle h with the equilibrium straight magnetic field, and all perturbations are functions...
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Karhunen-Loeve-based approach to tracking of rapidly fading wireless communication channels
PublicationWhen parameters of wireless communication channels vary at a fast rate, simple estimation algorithms, such as weighted least squares (WLS) or least mean squares (LMS) algorithms, cannot estimate them with the accuracy needed to secure the reliable operation of the underlying communication systems. In cases like this, the local basis function (LBF) estimation technique can be used instead, significantly increasing the achievable...
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Enriching novel dark chocolate with Bacillus coagulans as a way to provide beneficial nutrients
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Porcine myofibrillar proteins as potential precursors of bioactive peptides – an in silico study
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A standardised static in vitro digestion method suitable for food – an international consensus
PublicationSimulated gastro-intestinal digestion is widely employed in many fields of food and nutritional sciences, as conducting human trials are often costly, resource intensive, and ethically disputable. As a consequence, in vitro alternatives that determine endpoints such as the bioaccessibility of nutrients and non-nutrients or the digestibility of macronutrients (e.g. lipids, proteins and carbohydrates) are used for screening and building...
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Sugar matters: sugar moieties as reactivity-tuning factors in quercetin O-glycosides
PublicationQuercetin, one of the most abundant flavonoids in plant-based foods, commonly occurs in nature in various glycosylated forms. There is still a less explored aspect regarding the cause of its glycosides diversity, depending on the sugars moiety attached. This work focuses on four widespread quercetin glycosides—hyperoside, isoquercitrin, quercitrin and rutin—by testing property-tuning capacity of different sugar moieties and thus...
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Phenolic compounds from Nerium oleander leaves: microwave assisted extraction, characterization, antiproliferative and cytotoxic activities
PublicationA microwave-assisted extraction (MAE) method was used for the extraction of phenolic compounds from Nerium oleander leaves. The influence of variables such as ethanol concentration, microwave power, irradiation time and liquid/solid ratio on polyphenol extraction was modelled using a second-order regression equation based on response surface methodology (RSM). The optimal conditions for MAE were: extraction solvent 35% ethanol...
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Static in vitro digestion model adapted to the general older adult population: an INFOGEST international consensus
PublicationUnderstanding the mechanisms of food digestion is of paramount importance to determine the effect foods have on human health. Significant knowledge on the fate of food during digestion has been generated in healthy adults due to the development of physiologically-relevant in vitro digestion models. However, it appears that the performance of the oro-gastrointestinal tract is affected by ageing and that a model simulating the digestive...
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Paintings
PublicationThe painting as a curtain (...) A contradiction is therefore what constitutes a painting, and ambiguity is its right. As a young artist, I intuitively defined the work of art as a boundary. Over the years that intuition changed into a conviction that the particular form of art which is painting at the same time reveals and hides; it exists at this intersection of functions as a see-through curtain. We don’t know why there are some...
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Enhanced gas sensing by graphene-silicon Schottky diodes under UV irradiation
PublicationThe effect of ultraviolet (UV) or blue irradiation on graphene/n-doped silicon Schottky junctions toward gas sensing was investigated. Schottky diodes were subjected to oxidizing nitrogen dioxide (NO2, 1–3 ppm) and reducing tetrahydrofuran (THF, 50–200 ppm), showing significantly different responses observed on the currentvoltage (I-V) characteristics, especially under UV light (275 nm). NO2 affected the resistive part of the forward region...
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On the interspike-intervals of periodically-driven integrate-and-fire models
PublicationWe analyze properties of the firing map, which iterations give information about consecutive spikes, for periodically driven linear integrate-and-fire models. By considering locally integrable (thus in general not continuous) input functions, we generalize some results of other authors. In particular, we prove theorems concerning continuous dependence of the firing map on the input in suitable function spaces. Using mathematical...
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Multiresolution analysis and adaptive estimation on a sphere using stereographic wavelets
PublicationWe construct an adaptive estimator of a density function on d dimensional unit sphere Sd (d ≥ 2), using a new type of spherical frames. The frames, or as we call them, stereografic wavelets are obtained by transforming a wavelet system, namely Daubechies, using some stereographic operators. We prove that our estimator achieves an optimal rate of convergence on some Besov type class of functions by adapting to unknown smoothness....
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Studies of Nonlinear Sound Dynamics in Fluids Based on the Caloric Equation of State
PublicationThe sound speed and parameters of nonlinearity B/A, C/A in a fluid are expressed in terms of coefficients in the Taylor series expansion of an excess internal energy, in powers of excess pressure and density. That allows to conclude about features of the sound propagation in fluids, the internal energy of which is known as a function of pressure and density. The sound speed and parameters of nonlinearity in the mixture consisting...
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Self-Adaptive Mesh Generator for Global Complex Roots and Poles Finding Algorithm
PublicationIn any global method of searching for roots and poles, increasing the number of samples increases the chances of finding them precisely in a given area. However, the global complex roots and poles finding algorithm (GRPF) (as one of the few) has direct control over the accuracy of the results. In addition, this algorithm has a simple condition for finding all roots and poles in a given area: it only requires a sufficiently dense...
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Load-settlement characteristics of piles working in a group
PublicationLoad-settlement characteristic (Q-s) of an axially loaded pile can be empirically determined from a static pile load test or on the basis of calculations using, e.g. transfer functions or numerical methods (FEM). The transfer functions method usually rely on empirical data, i.e. the function parameters are determined on the basis of numerous pile test results. Thus this method takes into account pile installation technology and...
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Structure and evolution of the 4-helix bundle domain of Zuotin, a J-domain protein co-chaperone of Hsp70
PublicationThe J-domain protein Zuotin is a multi-domain eukaryotic Hsp70 co-chaperone. Though it is primarily ribosome-associated, positioned at the exit of the 60S subunit tunnel where it promotes folding of nascent polypeptide chains, Zuotin also has off-ribosome functions. Domains of Zuotin needed for 60S association and interaction with Hsp70 are conserved in eukaryotes. However, whether the 4-helix bundle (4HB) domain is conserved remains...
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FPGA Acceleration of Matrix-Assembly Phase of RWG-Based MoM
PublicationIn this letter, the field-programmable-gate-array accelerated implementation of matrix-assembly phase of the method of moments (MoM) is presented. The solution is based on a discretization of the frequency-domain mixed potential integral equation using the Rao-Wilton-Glisson basis functions and their extension to wire-to-surface junctions. To take advantage of the given hardware resources (i.e., Xilinx Alveo U200 accelerator card),...
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Diffusion equations with spatially dependent coefficients and fractal Cauer-type networks
PublicationIn this article, we formulate and solve the representation problem for diffusion equations: giving a discretization of the Laplace transform of a diffusion equation under a space discretization over a space scale determined by an increment h > 0, can we construct a continuous in h family of Cauer ladder networks whose constitutive equations match for all h > 0 the discretization. It is proved that for a finite differences discretization...
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Voltage and Current Unbalance Reduction in Power Networks with Distributed Generation and Electric Vehicles
PublicationThe current development of prosumer microsources and the expected spread of electric vehicles may cause the appearance of significant current and voltage unbalance in low-voltage (LV) networks. This unbalance, which is an unfavorable phenomenon, may occur when using single-phase photovoltaic (PV) microsources and single-phase home chargers for electric vehicles. This paper presents a proposal for the symmetrization of the LV network...
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Relativistic two-dimensional hydrogen-like atom in a weak magnetic field
PublicationA two-dimensional (2D) hydrogen-like atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first- and second-order Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The second-order calculations are...
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Geometry Parametric Model Order Reduction with Randomly Generated Projection Bases
PublicationIn this work, a reduced-order model for geometry parameters and fast frequency sweep is proposed. The Finite Element Method is used to solve time-harmonic Maxwell’s equations. Taking into account the electromagnetic field does not arbitrarily vary as a function of frequency and geometry parameters, a low dimension system manifold is identified. Thus, the original Finite Element problem can be approximated by a model of reduced...
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Application of regularized Savitzky–Golay filters to identification of time-varying systems
PublicationSavitzky–Golay (SG) filtering is a classical signal smoothing technique based on the local least squares approximation of the analyzed signal by a linear combination of known functions of time (originally — powers of time, which corresponds to polynomial approximation). It is shown that the regularized version of the SG algorithm can be successfully applied to identification of time-varying finite impulse response (FIR) systems....
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MutL protein as a constituent of vsp, ner and mmr repair systems
PublicationMutS and MutL proteins are renowned mostly for their functions in well-characterized, post-DNA replication mis- match repair system (MMR). However, there is growing evidence that MMR system is not the only field of action for these pro- teins. Moreover, the participation in MMR does not even have to be their primary function. There are some reports indicat- ing involvement of MutL in BER, NER and VSP (very short patch repair)....
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MUTL PROTEIN AS A COMMON CONSTITUENT OF VSP, BER, NER AND MMR REPAIR SYSTEMS
PublicationMutS and MutL proteins are renowned mostly for their functions in well-characterized, post-DNA replication mismatch repair system (MMR). However, there is growing evidence that MMR system is not the only field of action of these proteins. Moreover, involvement in MMR does not even have to be their primary function. There are some reports indicating involvement of MutL in BER, NER and VSP (very short patch repair). MutL protein...
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Adaptive Identification of Underwater Acoustic Channel with a Mix of Static and Time-Varying Parameters
PublicationWe consider the problem of identification of communication channels with a mix of static and time-varying parameters. Such scenarios are typical, among others, in underwater acoustics. In this paper, we further develop adaptive algorithms built on the local basis function (LBF) principle resulting in excellent performance when identifying time-varying systems. The main drawback of an LBF algorithm is its high complexity. The subsequently...
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Geochemical fractionation of organic matter in the Jurassic-Cretaceous Vaca Muerta shale, Argentina
PublicationSeveral studies have indicated the presence of more than one generation of bitumen that could be isolated from rocks through sequential extraction or after demineralization or both. Nabbefeld et al. (2010a) and Holman et al. (2012, 2014) termed bitumen obtained after solvent extraction from the undigested rock as “Bitumen I" and that obtained by extraction after demineralization of rock as “Bitumen II.” The occurrence of different...
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DESIGN AND EXECUTION ERRORS AS A CAUSE OF DAMAGE TO ANTI- ELECTROSTATIC FLOORING
PublicationApart from technological lines, industrial floors are a key element in the scope of maintaining the continuity of work of both production plants and logistics centers. The constantly developing industry of industrial flooring includes both classic design and technological flooring solutions, as well as specialist solutions used in facilities where technological processes or storage require system protection against static electricity....
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Invariant Measures for Uncountable Random Interval Homeomorphisms
PublicationA necessary and sufficient condition for the iterated function system { f (·, ω) | ω ∈ } with probability P to have exactly one invariant measure μ∗ with μ∗((0, 1)) = 1 is given. The main novelty lies in the fact that we only require the transformations f (·, ω) to be increasing homeomorphims, without any smoothness condition, nei- ther we impose conditions on the cardinality of . In particular, positive Lyapunov exponents conditions...
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Analiza Niezawodności Człowieka w Ramach Funkcji związanych z Bezpieczeństwem w Przykładowej Instalacji
PublicationW analizie bezpieczeństwa funkcjonalnego systemów sterowania i zabezpieczeń należy określić wymagany poziom nienaruszalności bezpieczeństwa SIL w procesie analizy ryzyka, a następnie zweryfikować ten poziom stosując odpowiednie metody modelowania probabilistycznego. Działania człowieka mogą mieć istotny wpływ na realizację funkcji bezpieczeństwa. Wpływ ten ocenia się na podstawie wyników analizy niezawodności człowieka HRA. W niniejszym...
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Analysis of hydrodynamic pressure fields of motorboats and pontoons in shallow water
PublicationThe article presents the results of calculations of the pressure fields generated by a motorboat at the bottom of a shallow sea. Calculations were made using the boundary elements method (BEM), arranged on the surface of the boat and the bottom of the sea. This method is described in [3], and applied on a free surface linearized boundary condition. Results for four different lengths of motorboats, from 2.85 m to 9.5 m, sea depth...
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The impact of technological and structural changes in the national economy on the labour-capital relations
PublicationThe aim of the research presented in this paper is to present the relations between labour and capital in the national economy, resulting from technological and structural changes taking place in the years 1991 to 2008. The structure of the paper is as follows. It first presents the functional determinants for the Polish economy in 1991-2008 affecting the phenomenon subject to study. Then it presents the preliminary analysis of...
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Co-simulation strategy of transient CFD and heat transfer in building thermal envelope based on calibrated heat transfer coefficients
PublicationThe paper presents a strategy to develop a fully transient numerical model of a heat transfer in building, using a transient CFD model of indoor air and a thermal envelope model, running in a co-simulation. The strategy relies on the utilization of RANS with a high-Re turbulence model and a wall function, which enables to use a coarse computational mesh limiting the computational time. Since wall functions give invalid heat transfer...
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Transport of dangerous goods by rail, and threats to the subsoil of the railway surface in the event of a disaster
PublicationIn Poland, in 2020, the mass of dangerous goods (loads) transported by rail was 26 151.06 thousand tone. This translated into the performance of 8 899 691.89 thousand tone - km of transport performance. In 2020, these figures accounted for 11.72% of the weight of goods transported by rail. The situation is similar in other countries around the world. With such a large volume of transport of dangerous...
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Mechanical behaviour of knit synthetic mesh used in hernia surgery
PublicationPurpose: There is a discussion in literature concerning mechanical properties and modelling of surgical meshes. An important feature of elastic modulus dependency on load history is taken into account in this paper, as implants are subjected to variable loading during human activity. The example of DynaMesh®-IPOM surgical implant is studied. Methods: The analysis is based on failure tension tests and cyclic loading and unloading...
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Molecular docking studies towards development of novel Gly-Phe analogs for potential inhibition of Cathepsin C (dipeptidyl peptidase I).
PublicationCathepsin C is a cysteine protease required for activation of various pro-inflammatory serine proteases and, essentially, is of interest as a therapeutic target. Cathepsin C coordinate system was employed as a model to study the interaction of some already available inhibitors of Cathepsin C. Compounds containing Gly-Phe fragment with functional groups at its ends were designed by knowledge based approach. Using AutoDock and...
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Color prediction from first principle quantum chemistry computations: a case of alizarin dissolved in methanol
PublicationThe electronic spectrum of alizarin (AZ) in methanol solution was measured and used as reference data for color prediction. The visible part of the spectrum was modelled by different DFT functionals within the TD-DFT framework. The results of a broad range of functionals applied for theoretical spectrum prediction were compared against experimental data by a direct color comparison. The tristimulus model of color expressed in terms...
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Synthesis, Structure, and Spectroscopic Properties of Calcium Thiophenecarboxylate Polymers. Structural Comparison with Analogous Lead Complexes
PublicationThree novel calcium coordination polymers [Ca(2tpCOO)2(2mpa)(H2O)]n (1), [Ca(3tpCOO)2(2mpa)(H2O)]n (2), and {[Ca(3tpacCOO)2(H2O)2]⋅⋅⋅H2O}n (3) (2tpCOO− or 3tpCOO− – thiophene-2- or thiophene-3-carboxylate, 3tpacCOO− – thiophene-3-acetate, 2mpa – 2-methylpropanal), were synthesised using a self-assembly method. The obtained polymers were characterised using SC-XRD, FTIR, UV-Vis DRS, thermogravimetric and luminescence analyses. The...
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Mathematical model defining volumetric losses of hydraulic oil compression in a variable capacity displacement pump
PublicationThe objective of the work is to develop the capability of evaluating the volumetric losses of hydraulic oil compression in the working chambers of high pressure variable capacity displacement pump. Volumetric losses of oil compression must be determined as functions of the same parameters, which the volumetric losses due to leakage, resulting from the quality of design solution of the pump, are evaluated as dependent on and also...
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Territorial Aspects of Entrepreneurial Activity in Polish Suburban Zones
PublicationGlobalization has led to an increased correlation and integration of various fields in modern civilization, including those connected with allocation of entrepreneurial functions. Connection, on a global scale, has shown an increased significance of worldwide corporations. Territorial allocation of the entrepreneurial function has become the subject of translocation and revaluation. Translocation can be understood as the change...
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DFT study of low-energy electron interaction with pyridine, pyrazine and their halo derivatives
PublicationIn this work, the density functional theory with B3LYP hybrid functional was employed to calculate quantities useful for estimating the behavior of pyridine, pyrazine and their derivatives monosubstituted with Cl or Br atom, when exposed to low-energy electron impact. Vertical electron affinities obtained in several Pople basis sets and in aug-cc-pVTZ basis set are reported. Although some of the investigated molecules do not form...
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The methylome and transcriptome of fetal skin: implications for scarless healing
PublicationAim: Fetal skin is known to heal without scarring. In mice, the phenomenon is observed until the 16–17 day of gestation – the day of transition from scarless to normal healing. The study aims to identify key methylome and transcriptome changes following the transition. Materials & methods: Methylome and transcriptome profiles were analyzed in murine dorsal skin using microarray approach. Results & conclusion: The genes associated...
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Calculating the Partition Coefficients of Organic Solvents in Octanol/Water and Octanol/Air
PublicationPartition coefficients define how a solute is distributed between two immiscible phases at equilibrium. The experimental estimation of partition coefficients in a complex system can be an expensive, difficult, and time-consuming process. Here a computational strategy to predict the distributions of a set of solutes in two relevant phase equilibria is presented. The octanol/water and octanol/air partition coefficients are predicted...
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Estimating inequality aversion from subjective assessments of the just noticeable differences in welfare
PublicationResearch background: In Economics, the concept of inequality aversion corresponds with the concept of risk aversion in the literature on making decision under uncertainty. The risk aversion is estimated on the basis of subjective reactions of people to various lottery prospects. In Economics, however, an efficient method of estimating inequality aversion has not been developed yet. Purpose of the article: The main aim of this paper...
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A new hyperbolic-polynomial higher-order elasticity theory for mechanics of thick FGM beams with imperfection in the material composition
PublicationA drawback to the material composition of thick functionally graded materials (FGM) beams is checked out in this research in conjunction with a novel hyperbolic‐polynomial higher‐order elasticity beam theory (HPET). The proposed beam model consists of a novel shape function for the distribution of shear stress deformation in the transverse coordinate. The beam theory also incorporates the stretching effect to present an indirect...
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TaRh 2 B 2 and NbRh 2 B 2 : Superconductors with a chiral noncentrosymmetric crystal structure
PublicationIt is a fundamental truth in solid compounds that the physical properties follow the symmetry of the crystal structure. Nowhere is the effect of symmetry more pronounced than in the electronic and magnetic properties of materials—even the projection of the bulk crystal symmetry onto different crystal faces is known to have a substantial impact on the surface electronic states. The effect of bulk crystal symmetry on the properties...
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Effects of Bromine Doping on the Structural Properties and Band Gap of CH3NH3Pb(I1–xBrx)3 Perovskite
PublicationAn experimental and theoretical study is reported to investigate the influence of bromine doping on CH3NH3Pb(I1−xBrx)3 perovskite for Br compositions ranging from x = 0 to x = 0.1, in which the material remains in the tetragonal phase. The experimental band gap is deduced from UV−vis absorption spectroscopy and displays a linear behavior as a function of bromine concentration. Density functional theory calculations are performed...
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Principles of target DNA cleavage and the role of Mg2+ in the catalysis of CRISPR–Cas9
PublicationAt the core of the CRISPR–Cas9 genome-editing technology, the endonuclease Cas9 introduces site-specific breaks in DNA. However, precise mechanistic information to ameliorate Cas9 function is still missing. Here, multimicrosecond molecular dynamics, free energy and multiscale simulations are combined with solution NMR and DNA cleavage experiments to resolve the catalytic mechanism of target DNA cleavage. We show that the conformation...
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Architektura współczesnego muzeum i jej znaczenie dla tożsamości krajobrazu miasta = The Architecture of Contemporary Museum and its Significance for the Identity of the Urban Landscape
PublicationArtykuł dotyczy architektury współczesnych muzeów, które pod koniec XX w. przeszły znaczący rozwój jako instytucje publiczne. Oprócz specyficznych wymagań technicznych, funkcjonalnych, estetycznych i kulturowych, ich charakterystyczną cechą jest wzrastające zapotrzebowanie na przestrzeń dodatkową służącą edukacji, odpoczynkowi, rozrywce i strefie komercyjnej (handlu i usług). Atrakcyjna przestrzeń publiczna zapewnia dostęp do wszystkich...
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Subcritical bifurcation of free elastic shell of biological cluster
PublicationIn this paper we will investigate symmetry-breaking bifurcation of equilibrium forms of biological cluster. A biological cluster is a two-dimensional analogue of a gas balloon. The cluster boundary is connected with its kernel by elastic links. The inside part is filled with compressed gas or fluid. Equilibrium forms of biological cluster can be found as solutions of a certain second order ordinary functional-differential equation...
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On weak solutions of boundary value problems within the surface elasticity of Nth order
PublicationA study of existence and uniqueness of weak solutions to boundary value problems describing an elastic body with weakly nonlocal surface elasticity is presented. The chosen model incorporates the surface strain energy as a quadratic function of the surface strain tensor and the surface deformation gradients up to Nth order. The virtual work principle, extended for higher‐order strain gradient media, serves as a basis for defining...