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Acceleration of the DGF-FDTD method on GPU using the CUDA technology
PublicationWe present a parallel implementation of the discrete Green's function formulation of the finite-difference time-domain (DGF-FDTD) method on a graphics processing unit (GPU). The compute unified device architecture (CUDA) parallel computing platform is applied in the developed implementation. For the sake of example, arrays of Yagi-Uda antennas were simulated with the use of DGF-FDTD on GPU. The efficiency of parallel computations...
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Playing the Sprint Retrospective: A Replication Study
PublicationThe Sprint Retrospective is a vehicle for continuous process improvement. Even though it is a well established agile practice, running effective retrospective meetings is challenging. There have been a lot of identified problems that commonly occur during these meetings. To address them, Przybyłek & Kotecka [20] successfully revitalized retrospective meetings by adopting collaborative games, which represent a powerful tool in improving...
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Gdańsk: a City of Solidarity and Freedom
PublicationOnly a few cities can claim that they have changed Europe and indeed the World. Gdańsk is privileged to be one of them. It is not a “caprice of history” that the Solidarity movement which, in the end, got the iron curtain torn, was born in this particular place. It is a logical consequence of ten centuries of the collective wisdom of the people that built Gdańsk and the region of Pomerania. The tragic assassination of the Mayor...
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Family business experience and the probability of starting a venture: gender differences in Poland
PublicationThe aim of this study is to analyse whether the experience of working in a family member’s business is related differently to the assessed probabilities of men and women starting their own new venture in the future. The research is conducted on a sample of 334 Polish undergraduate students. Poland is an efficiency-driven European economy with a substantial gender gap in entrepreneurship. The results obtained indicate that the relationship...
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An approach to constructing genuinely entangled subspaces of maximal dimension
PublicationGenuinely entangled subspaces (GESs) are the class of completely entangled subspaces that contain only genuinely multiparty entangled states. They constitute a particularly useful notion in the theory of entanglement but also have found an application, for instance, in quantum error correction and cryptography. In a recent study (Demianowicz and Augusiak in Phys Rev A 98:012313, 2018), we have shown how GESs can be efficiently...
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Topological, nonreciprocal, and multiresonant slow light beyond the time-bandwidth limit
PublicationTopologically protected transport has recently emerged as an effective means to address a recurring problem hampering the field of slow light for the past two decades: its keen sensitivity to disorders and structural imperfections. With it, there has been renewed interest in efforts to overcome the delay-time-bandwidth limitation usually characterizing slow-light devices, on occasion thought to be a fundamental limit. What exactly...
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How does climate change affect ice formation and presence in rivers, lakes and oceans, as well as its impact on infrastructure
PublicationIce season in rivers, lakes, seas and oceans is sensitive to climate change due to the high homologous temperature. Two vital aspects of the predicted climate change are increasing average air temperature and increasing variability in the weather. These cause delayed formation of ice, thinner ice and shorter duration of seasonal ice covers, the geographical ice margin to move further away from the equator, the perennial ice to...
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Comparison of three methods of EPR retrospective dosimetry in watch glass
PublicationIn this article we present results of our follow-up studies of samples of watch glass obtained and examined within a framework of international intercomparison dosimetry project RENEB ILC 2021. We present three methods of dose reconstruction based on EPR measurements of these samples: calibration method (CM), added dose method (ADM) and added dose&heating method (ADHM). The study showed that the three methods of dose reconstruction...
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Adopting collaborative games into Open Kanban
PublicationThe crucial element of any agile project is people. Not surprisingly, principles and values such as "Respect for people", "Communication and Collaboration", "Lead using a team approach", and "Learn and improve continuously" are an integral part of Open Kanban. However, Open Kanban has not provided any tools or techniques to aid the human side of software development. Moreover, as a Lean initiative, it is not as comprehensively...
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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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Uniform sampling in constrained domains for low-cost surrogate modeling of antenna input characteristics
PublicationIn this letter, a design of experiments technique that permits uniform sampling in constrained domains is proposed. The discussed method is applied to generate training data for construction of fast replacement models (surrogates) of antenna input characteristics. The modeling process is design-oriented with the surrogate domain spanned by a set of reference designs optimized with respect to the performance figures and/or operating...
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Role of miR-15b/16–2 cluster network in endometrial cancer: An in silico pathway and prognostic analysis
PublicationEndometrial cancer (EC) is the second most common cancer in women. A large number of human cancers exhibit dysregulation of microRNA expression including EC. MiR-15b/16–2 is one of the best-known miRNA clusters that is expressed in many types of cancer tissues. Herein, we analyzed the expression of individual miR-15b/16–2 cluster members, its paralogues, and their target network analysis, as well as their prognostic significance...
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Information-driven network resilience: Research challenges and perspectives
PublicationInternet designed over 40 years ago was originally focused on host-to-host message delivery in a best-effort manner. However, introduction of new applications over the years have brought about new requirements related with throughput, scalability, mobility, security, connectivity, and availability among others. Additionally, convergence of telecommunications, media, and information technology was responsible for transformation...
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Desensitization of glucosamine-6-phosphate synthase to inhibition by UDP-GlcNAc
PublicationGlucosamine-6-phosphate (GlcN-6-P) synthase, known also as L-Glutamine: D-fructose-6-phosphate amidotransferase, catalyzes the first committed step in the pathway leading to the ultimate formation of UDP-GlcNAc. The final product of this pathway is an activated precursor of numerous macromolecules containing amino sugars, including chitin and mannproteins in fungi, peptidoglycan and lipopolysaccharides in bacteria, and glycoproteins...
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Electron-scattering cross sections for selected alkyne molecules: Measurements and calculations
PublicationWe report cross-section results from experimental and theoretical studies on electron collisions with 1-butyne (HC≡C–CH2CH3) and acetylene (HC≡CH) molecules and from computations for a propyne (HC≡C–CH3) molecule. Absolute grand -total electron-scattering cross sections (TCSs) were measured at impact energies ranging from about 0.5 to 300 eV using the linear electron-transmission method. The TCS energy curve for 1-butyne has a...
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Membrane Sterols Modulate the Binding Mode of Amphotericin B without Affecting Its Affinity for a Lipid Bilayer
PublicationMembrane-active antibiotics are known to selectively target certain pathogens based on cell membrane properties, such as fluidity, lipid ordering, and phase behavior. These are in turn modulated by the composition of a lipid bilayer and in particular by the presence and type of membrane sterols. Amphotericin B (AmB), the golden standard of antifungal treatment, exhibits higher activity toward ergosterol-rich fungal membranes, which...
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How to meet when you forget: log-space rendezvous in arbitrary graphs
PublicationTwo identical (anonymous) mobile agents start from arbitrary nodes in an a priori unknown graph and move synchronously from node to node with the goal of meeting. This rendezvous problem has been thoroughly studied, both for anonymous and for labeled agents, along with another basic task, that of exploring graphs by mobile agents. The rendezvous problem is known to be not easier than graph exploration. A well-known recent result...
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White light thermoplasmonic activated gold nanorod arrays enable the photo-thermal disinfection of medical tools from bacterial contamination
PublicationThe outspread of bacterial pathogens causing severe infections and spreading rapidly, especially among hospitalized patients, is worrying and represents a global public health issue. Current disinfection techniques are becoming insufficient to counteract the spread of these pathogens because they carry multiple antibiotic-resistance genes. For this reason, a constant need exists for new technological solutions that rely on physical...
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The relationship between standard reduction potentials of catechins and biological activities involved in redox control
PublicationRedox homeostasis involves factors that ensure proper function of cells. The excess reactive oxygen species (ROS) leads to oxidative stress and increased risk of oxidative damage to cellular components. In contrast, upon reductive stress, insufficient ROS abundance may result in faulty cell signalling. It may be expected that dietary antioxidants, depending on their standard reduction potentials (E°), will affect both scenarios....
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Electrochemical performance of indium-tin-oxide-coated lossy-mode resonance optical fiber sensor
PublicationAnalysis of liquids performed in multiple domain, e.g., optical and electrochemical (EC), has recently focus significant attention. Our previous works have shown that a simple device based on indium-tin-oxide (ITO) coated optical fiber core may be used for optical monitoring of EC processes. At satisfying optical properties and thickness of ITO a lossy-mode resonance (LMR) effect can be obtained and used for monitoring of optical...
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Machine-Learning-Powered EM-Based Framework for Efficient and Reliable Design of Low Scattering Metasurfaces
PublicationPopularity of metasurfaces has been continuously growing due to their attractive properties including the ability to effectively manipulate electromagnetic (EM) waves. Metasurfaces comprise optimized geometries of unit cells arranged as a periodic lattice to obtain a desired EM response. One of their emerging application areas is the stealth technology, in particular, realization of radar cross section (RCS) reduction. Despite...
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Cost-Efficient Two-Level Modeling of Microwave Passives Using Feature-Based Surrogates and Domain Confinement
PublicationA variety of surrogate modelling techniques has been utilized in high-frequency design over the last two decades. Yet, the curse of dimensionality still poses a serious challenge in setting up re-liable design-ready surrogates of modern microwave components. The difficulty of the model-ing task is only aggravated by nonlinearity of circuit responses. Consequently, constructing a practically usable surrogate model, valid across...
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Performance of electrochemical immunoassays for clinical diagnostics of SARS-CoV-2 based on selective nucleocapsid N protein detection: Boron-doped diamond, gold and glassy carbon evaluation
PublicationThe 21st century has already brought us a plethora of new threats related to viruses that emerge in humans after zoonotic transmission or drastically change their geographic distribution or prevalence. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first spotted at the end of 2019 to rapidly spread in southwest Asia and later cause a global pandemic, which paralyzes the world since then. We have designed novel...
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Aluminium in glacial meltwater demonstrates an association with nutrient export (Werenskiöldbreen, Svalbard)
PublicationThe aluminium (Al) cycle in glacierised basins has not received a great deal of attention in studies of biogeochemical cycles. As Almay be toxic for biota, it is important to investigate the processes leading to its release into the environment. It has not yet been ascertained whether filterable Al (passing through a pore size of 0.45 m) is incorporated into biogeochemical cycles in glacierised basins. Our study aims to determine...
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Structure of liquid gold from tight-binding driven molecular-dynamics
PublicationPraca przedstawia wyniki symulacji ciekłego złota w nadkomórce periodycznej przy użyciu stworzonego przez autorów programu komputerowego, za pomocą połączonych metod dynamiki molekularnej (MD) i ciasnego wiązania (TB). Omówiono strukturę tak symulowanej cieczy, porównując ją z dostępnymi danymi doświadczalnymi oraz wynikami innych symulacji, pod kątem radialnej i kątowej funkcji rozkładu i elektronowej gęstości stanów.A tight-binding...
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Do new EU members have any chance of earning as much as Westerns do?
PublicationThis article examines the wage dispersion in the European Union in the last ten years (1996-2006). The research is motivated by the fact that New Members States (NMS) expected that wage convergence would occurred after their accession to the EU. At the same time Old Member States (OMS) have been increasingly concerned with the possibility that the EU enlargement could influence their local labor markets and wages through new channels...
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Exact resultant equilibrium conditions in the non-linear theory of branching and self-intersecting shells
PublicationWe formulate the exact, resultant equilibrium conditions for the non-linear theory of branching and self-intersecting shells. The conditions are derived by performing direct through-the-thickness integration in the global equilibrium conditions of continuum mechanics. At each regular internal and boundary point of the base surface our exact, local equilibrium equations and dynamic boundary conditions are equivalent, as expected,...
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Employees’ self-expansion as a mediator between perceived work conditions and work engagement and productive behaviors
PublicationThere has been increasing scientific interest in the relationships between self-perception and group identity development processes as well as the behavioural implications of these processes in organizational contexts. Recently, the concept of workplace self-expansion has been introduced to work and organizational psychology. That is, the self-expanding characteristics of work and the workplace have been related to job satisfaction...
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A Fail-Safe NVRAM Based Mechanism for Efficient Creation and Recovery of Data Copies in Parallel MPI Applications
PublicationThe paper presents a fail-safe NVRAM based mechanism for creation and recovery of data copies during parallel MPI application runtime. Specifically, we target a cluster environment in which each node has an NVRAM installed in it. Our previously developed extension to the MPI I/O API can take advantage of NVRAM regions in order to provide an NVRAM based cache like mechanism to significantly speed up I/O operations and allow to preload...
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COMPOSITION OF BIOACTIVE SECONDARY METABOLITES AND MUTAGENICITY OF SAMBUCUS NIGRA L. FRUIT AT DIFFERENT STAGES OF RIPENESS
PublicationThe relationship between the content of bioactive compounds and mutagenic activity of elderberry fruit at different stages of ripeness was investigated. Signifi cant differences in the antioxidant profi les (TLC, HPLC with post-column derivatization) and antioxidant activity (ABTS, DPPH, and FC tests) were observed for studied elderberry extracts. The more ripen the fruit at the time of harvest were, the higher the content of...
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Cost-efficient simulation-driven design of compact impedance matching transformers
PublicationIn this paper, an algorithmic framework for cost-efficient design optimization of miniaturized impedance matching transformers has been presented. Our approach exploits a bottom-up design that involves translating the overall design specifications for the circuit at hand to its elementary building blocks (here, compact microstrip resonant cells, CMRCs), as well as fast surrogate-assisted optimization of the cells followed by simulation-based...
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Rapid surrogate-assisted statistical analysis of compact microstrip couplers
PublicationIn this paper, a technique for low-cost statistical analysis and yield estimation of compact microwave couplers has been presented. The analysis is executed at the level of a fast surrogate model representing selected characteristic points of the coupler response that are critical to determine satisfaction/violation of the prescribed design specifications. Because of less nonlinear dependence of the characteristic points on geometry...
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Analytical Expression for the Time-Domain Green's Function of a Discrete Plane Wave Propagating in the 3-D FDTD Grid
PublicationIn this paper, a closed-form expression for the time-domain dyadic Green’s function of a discrete plane wave (DPW) propagating in a 3-D finite-difference time-domain (FDTD) grid is derived. In order to verify our findings, the time-domain implementation of the DPW-injection technique is developed with the use of the derived expression for 3-D total-field/scattered-field (TFSF) FDTD simulations. This implementation requires computations...
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Characterization of metabolites in different kiwifruit varieties by NMR and fluorescence spectroscopy
PublicationIt is known from our previous studies that kiwifruits, which are used in common human diet, have preventive properties of coronary artery disease. This study describes a combination of 1H NMR spectroscopy, multivariate data analyses and fluorescence measurements in differentiating of some kiwifruit varieties, their quenching and antioxidant properties. A total of 41 metabolites were identified by comparing with literature data...
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From Linear Classifier to Convolutional Neural Network for Hand Pose Recognition
PublicationRecently gathered image datasets and the new capabilities of high-performance computing systems have allowed developing new artificial neural network models and training algorithms. Using the new machine learning models, computer vision tasks can be accomplished based on the raw values of image pixels instead of specific features. The principle of operation of deep neural networks resembles more and more what we believe to be happening...
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Similarities and Differences Between the Vertex Cover Number and the Weakly Connected Domination Number of a Graph
PublicationA vertex cover of a graph G = (V, E) is a set X ⊂ V such that each edge of G is incident to at least one vertex of X. The ve cardinality of a vertex cover of G. A dominating set D ⊆ V is a weakly connected dominating set of G if the subgraph G[D]w = (N[D], Ew) weakly induced by D, is connected, where Ew is the set of all edges having at least one vertex in D. The weakly connected domination number γw(G) of G is the minimum cardinality...
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Nuclear magnetic shielding constants of Dirac one-electron atoms in some low-lying discrete energy eigenstates
PublicationWe present tabulated data for the nuclear magnetic shielding constants (σ) of the Dirac one-electron atoms with a pointlike, motionless and spinless nucleus of charge Ze. Utilizing the exact general analytical formula for σ derived by us (Stefańska, 2016) valid for an arbitrary discrete energy eigenstate, we have computed the numerical values of the magnetic shielding factors for the ground state and for the first and the second...
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Spectroscopic and magnetic studies of highly dispersible superparamagnetic silica coated magnetite nanoparticles
PublicationSuperparamagnetic behavior in aqueously well dispersible magnetite core-shell Fe3O4@SiO2 nanoparticles is presented. The magnetic properties of core-shell nanoparticles were measured with use of the DC, AC magnetometry and EPR spectroscopy. Particles were characterized by HR-TEM and Raman spectroscopy, showing a crystalline magnetic core of 11.5 ± 0.12 nm and an amorphous silica shell of 22 ± 1.5 nm in thickness. The DC, AC magnetic...
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Knowledge risks - towards a taxonomy
PublicationThe paper aims to identify, describe and analyse knowledge risks organisations might face and based on this, proposes a taxonomy of knowledge risks. To achieve this goal, a literature review was conducted. After the analysis of the existing material, it was possible to divide knowledge risks into two categories: internal (originating from the inside of the organisation) and external (originating from the outside of the organisation)....
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Kształtowanie tożsamości na przykładzie małych miast województwa pomorskiego
PublicationSmall towns form an important element of the landscape, economy, both social and cultural life of our regions. Moreover, the way they develop determine regional indicators of the quality of life. These centers take today attempt to redefine its role and place in the spatial structures of the region, looking for new impulses and development opportunities to improve the living conditions of the local public. They have deeply divergent...
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Power augmentation of PGE Gorzow's gas turbine by steam injection - thermodynamic overview
PublicationThe impact of steam injection upon a gas turbine and a combined power plant performance has been investigated. This article describes and summarizes possibilities of modification for current gas turbine in PGE Gorzow power plant into the Cheng cycle. Our modification deals with a thermal cycle, in which steam produced in a heat recovery steam generator is injected into the gas turbine's combustion chamber. It has been proved that...
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Distillery Wastes as External Carbon Sources for Denitrification in Municipal Wastewater Treatment Plants
PublicationW pracy przedstawiono wyniki badań nad zastosowaniem półproduktów oraz produktów odpadowych z gorzelni i destylarni, jako potencjalne źródło zewnętrznego węgla organicznego w celu poprawy denitryfikacji w systemach z biologicznym usuwaniem związków biogennych. W celu porównania efektywności trzech badanych substancji (oleje fuzlowe, odcieki i syrop) wykonano testy na szybkość redukcji azotanów (z ang. NUR) oraz szybkość zużycia...
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Quantum-correlation breaking channels, broadcasting scenarios, and finite Markov chains
PublicationOne of the classical results concerning quantum channels is the characterization of entanglementbreakingchannels [M. Horodecki et al., Rev. Math. Phys 15, 629 (2003)]. We address the questionwhether there exists a similar characterization on the level of quantum correlations which may gobeyond entanglement. The answer is fully affirmative in the case of breaking quantum correlationsdown to the, so called, QC (Quantum-Classical)...
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Decisional DNA and Optimization Problem
PublicationMany researchers have proved that Decisional DNA (DDNA) and Set of Experience Knowledge Structure (SOEKS or SOE) is a technology capable of gathering information and converting it into knowledge to help decision-makers to make precise decisions in many ways. These techniques have a feature to combine with different tools, such as data mining techniques and web crawlers, helping organization collect information from different sources...
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Robustness of quantum-randomness expansion protocols in the presence of noise
PublicationIn this paper we investigate properties of several randomness generation protocols in the device independent framework. Using Bell-type inequalities it is possible to certify that the numbers generated by an untrusted device are indeed random. We present a selection of certificates which guarantee two bits of randomness for each run of the experiment in the noiseless case and require the parties to share a maximally entangled state....
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Fast Multi-Objective Optimization of Narrow-Band Antennas Using RSA Models and Design Space Reduction
PublicationComputationally efficient technique for multi-objective design optimization of narrow-band antennas is presented. In our approach, the corrected low-fidelity antenna model (obtained through coarse-discretization EM simulations) is enhanced using frequency scaling and response correction, sampled, and utilized to obtain a fast response surface approximation (RSA) antenna surrogate. The RSA model is constructed in the reduced design space....
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Znaczenie płci w procesie zakupu marek własnych sieci handlowych – analiza wielogrupowa
PublicationThe purpose of the article is to analyze the differences in the behavior of men and women in the process of purchasing store brands (SBs). Using an established conceptual model, we intended to identify differences, depending on gender of buyers, in the size of the effects of store image and brand price-image on perceived risk and subsequently on store brand purchase intention. A total of 652 respondents participated in the study....
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A Canonical Switched Capacitor DC-DC Converter. A look at how the historical SC synthesis problem is getting solved
PublicationWe reconsider a solution to the historical problem in switched capacitor (SC) DC-DC converter synthesis. Specifically, we retackle the problem of constructing an SC twophase network realizing arbitrary voltage conversion ratio within rational bounds defined. Theoretical foundations are available in our earlier research [3] where a nonconstructive proof of existence was given. We briefly review and comment on known circuit solutions...
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Structure and computationally-efficient simulation-driven design of compact UWB monopole antenna
PublicationIn this letter, a structure of a small ultra-wideband (UWB) monopole antenna, its design optimization procedure as well as experimental validation are presented. According to our approach, antenna compactness is achieved by means of a meander line for current path enlargement as well as the two parameterized slits providing additional degrees of freedom that help to ensure good impedance matching. For the sake of reliability, the...
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Applying Decisional DNA to Internet of Things: The Concept and Initial Case Study
PublicationIn this article, we present a novel approach utilizing Decisional DNA to help the Internet of Things capture decisional events and reuse them for decision making in future operations. The Decisional DNA is a domain-independent, standard and flexible knowledge representation structure that allows its domains to acquire, store, and share experiential knowledge and formal decision events in an explicit way. We apply this approach...