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EXPERIMENTAL AND NUMERICAL INVESTIGATION ON SPECIMEN GEOMETRY EFFECT ON THE CTOD VALUE FOR VL-E36 SHIPBUILDING STEEL
PublicationThere are special cases in the marine industry, where additional material tests, such as the fracture toughness test, must be performed. Additional fracture toughness tests, such as CTOD (Crack Tip Opening Displacement), are typically performed on three-point bend specimens. The dimension that defines all the specimen dimensions is the thickness of the material to be tested. It is recommended by classification societies (e.g. DNVGL)...
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Effectiveness of toluene separation from gas phase using supported ammonium ionic liquid membrane
PublicationAmmonium ionic liquids (ILs) are relatively cheap in synthesis and environmentally benign and despite that they have been very rarely used in gas separation. In this research we used several ammonium ILs as liquid membranes for removal of residual toluene from gas phase. Ionic liquids used in this study were composed of bis(trifluoromethylsulfonyl)imide anion [Tf2N] and trimethylbutylammonium [N1114], trietylbutylammonium [N2224],...
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Analytical solution of non-stationary heat conduction problem for two sliding layers with time-dependent friction conditions
PublicationIn this article we conduct an overview of various types of thermal contact conditions at the sliding interface. We formulate a problem of non-stationary heat conduction in two sliding layers with generalized thermal contact conditions allowing for dependence of the heat-generation coefficient and contact heat transfer coefficient on time. We then derive an analytical solution of the problem by constructing a special coordinate...
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Relationship between semi- and fully-device-independent protocols
PublicationWe study the relation between semi and fully device independent protocols. As a tool, we use the correspondence between Bell inequalities and dimension witnesses. We present a method for converting the former into the latter and vice versa. This relation provides us with interesting results for both scenarios. First, we find new random number generation protocols with higher bit rates for both the semi and fully device independent...
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Design Evolution of the Ultrasonic Piezoelectric Motor Using Three Rotating Mode Actuators
PublicationThe development process and experimental investigation of the multicell piezoelectric motor is presented in this paper. The proposed design consists of three individual cells integrated into the stator, double rotor, and a preload system. Those elements are combined into a symmetrical structure of the motor. The two new prototypes have been designed, simulated and tested. Finite element numerical analysis is carried out to obtain...
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Use of pyridinium and pyrrolidinium ionic liquids for removal of toluene from gas streams
PublicationSeparation of toluene from a toluene/N2 gas mixture using supported liquid membranes based on a series of pyridinium (1-butylpyridinium- bis(trifluoromethylsulfonyl)imide - [C4Py][Tf2N], 1-hexylpyridinium trifluoromethanesulfone [C6Py][Tf2N]) and pyrrolidinium (1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide - [C4Pyrr][Tf2N], 1-hexyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide - [C6Pyrr][Tf2N], 1-butyl-1-methylpyrrolidinium...
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Jeffreys heat conduction in coupled semispaces subjected to interfacial heating
PublicationA Jeffreys heat conduction problem for coupled semispaces subjected to the action of an interfacial heat source was defined. An analytical solution of the problem was derived for a polynomial specific power of the heat source using the Laplace transform approach. The asymptotic and parametric analysis was performed for different ratios of thermal conductivities , thermal diffusivities , thermal relaxation times and coefficients...
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A Compact Basis for Reliable Fast Frequency Sweep via the Reduced-Basis Method
PublicationA reliable reduced-order model (ROM) for fast frequency sweep in time-harmonic Maxwell’s equations by means of the reduced-basis method is detailed. Taking frequency as a parameter, the electromagnetic field in microwave circuits does not arbitrarily vary as frequency changes, but evolves on a very low-dimensional manifold. Approximating this low-dimensional manifold by a low dimension subspace, namely, reduced-basis space, gives...
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Equitable coloring of hypergraphs
PublicationA hypergraph is equitablyk-colorable if its vertices can be partitioned into k sets/colorclasses in such a way that monochromatic edges are avoided and the number of verticesin any two color classes differs by at most one. We prove that the problem of equitable 2-coloring of hypergraphs is NP-complete even for 3-uniform hyperstars. Finally, we apply the method of dynamic programming for designing a polynomial-time algorithm to...
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Optimization of Execution Time under Power Consumption Constraints in a Heterogeneous Parallel System with GPUs and CPUs
PublicationThe paper proposes an approach for parallelization of computations across a collection of clusters with heterogeneous nodes with both GPUs and CPUs. The proposed system partitions input data into chunks and assigns to par- ticular devices for processing using OpenCL kernels defined by the user. The sys- tem is able to minimize the execution time of the application while maintaining the power consumption of the utilized GPUs and...
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Self-standing Nanoarchitectures
PublicationDespite there are structures invisible for the human eye, they mastered the world of advanced electronic devices, sensors, novel cosmetics or drugs. When the dimensions of the materials go down to the nanometres scale, their properties change dramatically comparing to the observable objects. Because of their tiny size, they gained the name of nanomaterials but simultaneously their importance has significantly grown up. Nanomaterials...
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Symbiosis of Art and Technology – From Renaissance to Interactive Art,
PublicationThe article presents the mutual relations between art and technology from the Renaissance to the interactive art of today. It indicates important factors influencing the possibilities of imaging and interpreting reality by artists, ranging from the development of oil painting techniques, linear perspective, the invention of printing and photography, to achievements related to the development of information technologies (computers,...
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REVISING ENTREPRENEURIAL ORIENTATION (EO) IN SOCIAL ENTREPRENEURSHIP, QUALITATIVE EVIDENCE FROM WORK INTEGRATION SOCIAL ENTERPRISES (WISES) FROM POLAND
PublicationEntrepreneurial behaviour and entrepreneurial orientation (EO) of (commercial) entrepreneurship. have received significant scholarly attention in entrepreneurship and management research However, there are insufficient attempts discussing such behaviour and EO in non-profit, and particularly social entrepreneurship context, arguing that EO is higher in such contexts, or remains the same, some new EO dimensions are proposed, existing...
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Design of Microstrip UWB Balun Using Quasi-TEM Approach Aided by the Artificial Neural Network
PublicationThe design procedure for UWB balun realized in the microstrip technology is proposed in the paper. The procedure applies Artificial Neural Network which corrects the dimensions of the approximate design found by appropriate scaling of the dimensions of the prototype. The scale coefficients for longitudinal and transverse dimensions of microstrip lines are determined from electromagnetic modeling based on transmission line equations....
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The dynamic signature verification using population-based vertical partitioning
PublicationThe dynamic signature is an attribute used in behavioral biometrics for verifying the identity of an individual. This attribute, apart from the shape of the signature, also contains information about the dynamics of the signing process described by the signals which tend to change over time. It is possible to process those signals in order to obtain descriptors of the signature characteristic of an individual user. One of the methods...
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A SEARCH OF AN INDUCER GEOMETRY THAT IS BENEFICIAL FOR LIFTING PARAMETERS OF A LIFTED OBJECT OF A SELECTED SHAPE
PublicationThe literature describes acoustic levitation phenomena with the utilization of air squeeze film between the vibrating inducer and the lifted object. The objective of the study is to determine the shape of the inducer with vibration characteristics that would allow the levitation of an object of the assumed geometry. In this paper, the influence of the dimension ratio of the inducer on the frequency of the first mode of vibration...
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Revising Entrepreneurial Orientation Construct in Social Enterprise
PublicationEntrepreneurial behavior and entrepreneurial orientation (EO) have received significant scholarly attention in entrepreneurship and management research, but mainly in the commercial context. However, some attempts discussing such behavior and EO among non-profit organizations, but limited in the social enterprise context. The literature argues that EO is higher in such contexts (Zahra, Gedajlovic, Neubaum & Shulman, 2009; Lumpkin,...
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Otrzymywanie i właściwości przeciworostowych powłok poli(estrowo-uretanowych)
PublicationW pracy przedstawiono wyniki badań dotyczące otrzymania poliuretanowej powłoki przeciwporostowej, którą uzyskano metodą prepolimerową, a jako czynnik przeciwporostowy zastosowano pirition cynku oraz tlenek miedzi (I). Otrzymane powłoki poddano ekspozycji w wodzie morskiej a następnie przeprowadzono analizę ich mikrostruktury za pomocą mikroskopu optycznego. Z przeprowadzonych badań wynika, iż głównym czynnikiem decydującym o skuteczności...
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Expedited Geometry Scaling of Compact Microwave Passives by Means of Inverse Surrogate Modeling
PublicationIn this paper, the problem of geometry scaling of compact microwave structures is investigated. As opposed to conventional structures (i.e., constructed using uniform transmission lines), re-design of miniaturized circuits (e.g., implemented with artificial transmission lines, ATSs) for different operating frequencies is far from being straightforward due to considerable cross-couplings between the circuit components. Here, we...
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Efektywność przewodowego transportu paliw gazowych. Część 1
PublicationW pracy przeprowadzono badanie możliwości podwyższenia efektywności transportu rurociągowego gazu ziemnego. Przeanalizowano różnorodne aspekty z zakresu procedur projektowania. Zaproponowano modele określania kosztów kapitałowych (inwestycyjnych) i kosztów zmiennych. Określono równania jednostkowych kosztów całkowitych (rocznych), które poddano „quasi-optymalizacji”, w celu wyznaczenia średnic racjonalnych dla gazociągów.
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Efektywność przewodowego transportu paliw gazowych. Część 2
PublicationW pracy przeprowadzono badanie możliwości podwyższenia efektywności transportu rurociągowego gazu ziemnego. Przeanalizowano różnorodne aspekty z zakresu procedur projektowania. Zaproponowano modele określania kosztów kapitałowych (inwestycyjnych) i kosztów zmiennych. Określono równania jednostkowych kosztów całkowitych (rocznych), które poddano „quasi-optymalizacji”, w celu wyznaczenia średnic racjonalnych dla gazociągów.
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Perfect thermal contact of hyperbolic conduction semispaces with an interfacial heat source
PublicationThe problem of thermal contact between two bodies with a heat source at their interface presents great scientific and practical interest. On the time scale of a nanosecond or shorter, heat propagation should be considered in the form of thermal waves of finite speeds. This study investigated the thermal behaviour of hyperbolic conduction semispaces in perfect thermal contact subjected to the action of an interfacial heat source....
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Sizes of iron hydroxide particles formed during ferric coagulation processes
PublicationThe aim of the study was to apply laser granulometer for measuring sizes of particles formed in iron-based coagulation process in water, which did not contain significant amounts of organic compounds. The research was conducted using tap water, obtained from underground sources. Iron sulfate in doses of 2.0–10.0 mgFe L–1 was added to water. During initial stage of flocculation, iron hydroxide particles reached dimensions between...
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Integrated model for the fast assessment of flood volume: Modelling – management, uncertainty and sensitivity analysis
PublicationThe specific flood volume is an important criterion for assessing the performance of sewage networks. It has been shown that its value is greatly influenced by the layout of the sewers in the catchment area, which is usually expressed by a fractal dimension. Currently, only mechanistic models (such as SWMM) enable the determination of the impact of the layout of the sewers on flooding volume, but they require additional and robust...
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Takagi-Sugeno Fuzzy Model of Dissolved Oxygen Concentration Dynamics in a Bioreactor at WWTP
PublicationThe importance of dissolved oxygen concentration controlinaerationtanksofabioreactoratflow-throughwastewater treatment plant (WWTP) can easily be justified by technological requirements as well as simple economics. Firstly, appropriate levels of dissolved oxygen concentration are essential for the vitality of microorganisms that comprise the bioreactor. Secondly, the costs of dissolved oxygen concentration control related to the...
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Investigating Feature Spaces for Isolated Word Recognition
PublicationMuch attention is given by researchers to the speech processing task in automatic speech recognition (ASR) over the past decades. The study addresses the issue related to the investigation of the appropriateness of a two-dimensional representation of speech feature spaces for speech recognition tasks based on deep learning techniques. The approach combines Convolutional Neural Networks (CNNs) and timefrequency signal representation...
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Removal of persistant organic pollutants from landfill leachates treated in three constructed wetland systems
PublicationThe objective of the study was assessment of occurrence and removal of two groups of persistent organic pollutants: polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in landfill leachate (LL) treated in three constructed wetland systems (CWs) of different construction and flow regime. Two subsurface flow systems (SSF) were analyzed: one with horizontal flow and the second one consisting of two vertical...
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Topical delivery of pharmaceutical and cosmetic macromolecules using microemulsion systems
PublicationMicroemulsions are transparent, thermodynamically stable colloidal systems. Over the recent years, they have been increasingly investigated due to their potential as skin delivery vehicles for a wide range of drug molecules. The nanoscale particle size and the specificity of microemulsion components are the main features determining the skin permeation process. However, in order to effectively cross the skin barrier, the active...
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Expedited Globalized Antenna Optimization by Principal Components and Variable-Fidelity EM Simulations: Application to Microstrip Antenna Design
PublicationParameter optimization, also referred to as design closure, is imperative in the development of modern antennas. Theoretical considerations along with rough dimension adjustment through supervised parameter sweeping can only yield initial designs that need to be further tuned to boost the antenna performance. The major challenges include handling of multi-dimensional parameter spaces while accounting for several objectives and...
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Discrete element method simulations of fracture in concrete under uniaxial compression based on its real internal structure
PublicationThe paper describes experimental and numerical results of concrete fracture under quasi-static uniaxial compression. Experimental uniaxial compression tests were performed on concrete cubic specimens. Fracture in concrete was detected at the aggregate level by means of three non-destructive methods: three-dimensional X-ray microcomputed tomography, two-dimensional scanning electron microscope and manual two-dimensional digital...
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Combinatorial scheme of finding minimal number of periodic points for smooth self-maps of simply connected manifolds
PublicationLet M be a closed smooth connected and simply connected manifold of dimension m at least 3, and let r be a fixed natural number. The topological invariant D^m_r [f], defined by the authors in [Forum Math. 21 (2009), 491-509], is equal to the minimal number of r-periodic points in the smooth homotopy class of f, a given self-map of M. In this paper, we present a general combinatorial scheme of computing D^m_r [f] for arbitrary dimension...
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Influence of Storage Time and Temperature on the Toxicity, Endocrine Potential, and Migration of Epoxy Resin Precursors in Extracts of Food Packaging Materials
PublicationThe aim of the present study was to establish a standard methodology for the extraction of epoxy resin precursors from several types of food packages (cans, multi-layered composite material, and cups) with selected simulation media (distilled water, 5% ethanol, 3% dimethyl sulfoxide, 5% acetic acid, artificial saliva) at different extraction times and temperatures (factors). Biological analyses were conducted to determine the acute...
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On Unsupervised Artificial-Intelligence-Assisted Design of Antennas for High-Performance Planar Devices
PublicationDesign of modern antenna structures is a challenging endeavor. It is laborious, and heavily reliant on engineering insight and experience, especially at the initial stages oriented towards the devel-opment of a suitable antenna architecture. Due to its interactive nature and hands-on procedures (mainly parametric studies) for validating suitability of particular geometric setups, typical antenna development requires many weeks...
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Exploring the factor structure and the validity of the abbreviated Basic and Earning Self-Esteem Scales
PublicationThe original longer versions (Forsman & Johnson, 1996) and abbreviated versions of the Basic and Earning Self-Esteem Scales have been used in clinical and non-clinical settings, but little is known about the factor structure and the validity of these scales in their abbreviated forms. The original longer versions of the scales comprise several dimensions, but both abbreviated versions of the scales have been interpreted as if they...
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Proximity and the Cluster Organization
PublicationIncluding the category of proximity in theoretical considerations and empirical analyzes in cluster organizations is an attempt to integrate existing approaches to understand and explain the specificity of inter-organizational cooperation developed in geographical proximity. The importance of geographical proximity to create a competitive advantage is emphasized in all theories on the establishment and development of industrial...
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Socioemotional Wealth (SEW) of Family Firms and CEO Behavioral Biases in the Implementation of Sustainable Development Goals (SDGs)
PublicationAgreed upon by the UN member states, Agenda 2030 assumes joint action for long- term sustainable development. These actions are focused on the implementation of 17 Sustainable Development Goals (SDGs), where actions are assumed to lead to the suppression of negative externalities of human activity. It is stressed that the objectives of sustainable development can only be achieved through deep institutional changes in most dimensions...
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Novel Tools as New Challenges to HRM Communicational Practices (and the Increasingly Important Social Role of the Manager)
PublicationEach communicational process consists inseparably of three aspects: the linguistic (which means the whole language content of the message), technical (which states the form of the message) and the social (meaning social relations, emotions, behaviours). The recent COVID-19 pandemic deeply influenced several layers of our lives. But the main aim of this chapter is to focus on the communicational processes that normally take place...
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Accelerated Re-Design of Antenna Structures Using Sensitivity-Based Inverse Surrogates
PublicationThe paper proposes a novel framework for accelerated re-design (dimension scaling) of antenna structures using inverse surrogates. The major contribution of the work is a sensitivity-based model identification procedure, which permits a significant reduction of the number of reference designs required to render the surrogate. Rigorous formulation of the approach is supplemented by its comprehensive numerical validation using a...
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Structural and Temporal Topic Models of Feedbacks on Service Quality – A Path to Theory Development?
PublicationThere is growing interest in applying computational methods in analysing large amount of data without sacrificing rigour in Information Systems research. In this paper, we demonstrate how the use of structural and temporal topic modelling can be employed to produce insights of both theoretical and practical importance from the analysis of textual comments on the quality of services in hospitals. As a first step, we revealed the...
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Solution of the dike-break problem using finite volume method and splitting technique
PublicationIn the paper the finite volume method (FVM) is presented for the solution of two-dimensional shallow water equations. These equations are frequently used to simulate the dam-break and dike-break induced flows. The applied numerical algorithm of FVM is based on the wave-propagation algorithm which ensures a stable solution and simultaneously minimizes the numerical errors. The dimensional decomposition according to the coordinate...
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A Workflow Application for Parallel Processing of Big Data from an Internet Portal
PublicationThe paper presents a workflow application for efficient parallel processing of data downloaded from an Internet portal. The workflow partitions input files into subdirectories which are further split for parallel processing by services installed on distinct computer nodes. This way, analysis of the first ready subdirectories can start fast and is handled by services implemented as parallel multithreaded applications using multiple...
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On Computational Aspects of Greedy Partitioning of Graphs
PublicationIn this paper we consider a problem of graph P-coloring consisting in partitioning the vertex set of a graph such that each of the resulting sets induces a graph in a given additive, hereditary class of graphs P. We focus on partitions generated by the greedy algorithm. In particular, we show that given a graph G and an integer k deciding if the greedy algorithm outputs a P-coloring with a least k colors is NP-complete for an infinite...
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Playback detection using machine learning with spectrogram features approach
PublicationThis paper presents 2D image processing approach to playback detection in automatic speaker verification (ASV) systems using spectrograms as speech signal representation. Three feature extraction and classification methods: histograms of oriented gradients (HOG) with support vector machines (SVM), HAAR wavelets with AdaBoost classifier and deep convolutional neural networks (CNN) were compared on different data partitions in respect...
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Projektowanie układów ramowych z zastosowaniem analizy wrażliwości
PublicationW pracy przedstawiono przykład projektowania układów ramowych z zastosowaniem analizy wrażliwości. Rozważane układy ramowe rozwiązano autorskim programem napisanym w środowisku MATLAB, metodą elementów skończonych. Badano wpływ zmiany modułu Younga oraz wpływ zmiany wielkości przekroju poprzecznego na wybrane przemieszczenia ramy. Przedstawiono wyniki dla analizy wrażliwości jedno i wieloparametrycznej.
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Comparative analysis of thermodynamic cycles of selected nuclear ship power plants with high-temperature helium-cooled nuclear reactor
PublicationThis paper presents a comparative analysis of thermodynamic cycles of two ship power plant systems with a high-temperature helium- cooled nuclear reactor. The first of them is a gas system with recuperator , in which classical gas chamber is substituted for a HTGR reactor (High Temperature Gas-cooled Reactor) . The second of the considered cycles is a combined gas-steam system where working medium flux from gas turbine outlet...
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Mechanism-based inactivation of human cytochrome P450 1A2 and 3A4 isoenzymes by antitumor triazoloacridinone C-1305.
Publication5-Dimethylaminopropylamino-8-hydroxytriazoloacridinone, C-1305, is a promising antitumor therapeutic agent with high activity against several experimental tumors. It was determined to be a potent and selective inhibitor of liver microsomal and human recombinant cytochrome P450 (CYP) 1A2 and 3A4 isoenzymes. Therefore, C-1305 might modulate the effectiveness of other drugs used in multidrug therapy. The objective of this study was...
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Necessary and Sufficient Condition for State-Independent Contextual Measurement Scenarios
PublicationThe problem of identifying measurement scenarios capable of revealing state-independent contextuality in a given Hilbert space dimension is considered. We begin by showing that for any given dimension d and any measurement scenario consisting of projective measurements, (i) the measure of contextuality of a quantum state is entirely determined by its spectrum, so that pure and maximally mixed states represent the two extremes...
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Experimental verification and comparison of mode shape-based damage detection methods
PublicationThis paper presents experimental verification and comparison of damage detection methods based on changes in mode shapes such as: mode shape curvature (MSC), modal assurance criterion (MAC), strain energy (SE), modified Laplacian operator (MLO), generalized fractal dimension (GFD) and Wavelet Transform (WT).
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Particle Shape Effect on Macroscopic Behaviour of Underground Structures: Numerical and Experimental Study
PublicationThe mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete Element Methods....
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Particle Shape Effect on Macroscopic Behaviour of Underground Structures: Numerical and Experimental Study
PublicationAbstract: The mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also on the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete...