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The investigation of polyester composites filled by modified bentonite
PublicationPraca dotyczy zagospodarowania odpadów poliestrowo-szklanych przez wytworzenie kompozytów z ich użyciem oraz żywicy poliestrowej, mączki dolomitowej i nanonapełniacza. Wykazano, ze dodatek 2% nanonapełniacza do do kompozytów poliestrowych zawierających 15% masowych odpadów pozwala na uzyskanie materiału wykazującego korzystne właściwości wytrzymałościowe. Proponowany sposób modyfikacji kompozytów poliestrowych jest nowym rozwiązaniem...
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Practical Approach to Large-Scale Electronic Structure Calculations in Electrolyte Solutions via Continuum-Embedded Linear-Scaling Density Functional Theory
PublicationWe present the implementation of a hybrid continuum-atomistic model for including the effects of a surrounding electrolyte in large-scale density functional theory (DFT) calculations within the Order-N Electronic Total Energy Package (ONETEP) linear-scaling DFT code, which allows the simulation of large complex systems such as electrochemical interfaces. The model represents the electrolyte ions as a scalar field and the solvent...
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Implementing artificial intelligence in forecasting the risk of personal bankruptcies in Poland and Taiwan
PublicationResearch background: The global financial crisis from 2007 to 2012, the COVID-19 pandemic, and the current war in Ukraine have dramatically increased the risk of consumer bankruptcies worldwide. All three crises negatively impact the financial situation of households due to increased interest rates, inflation rates, volatile exchange rates, and other significant macroeconomic factors. Financial difficulties may arise when the...
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Study of the Resistance to Influence of Aggressive Liquids on Concrete with Lightweight Aggregate
PublicationThe corrosion of the structure of concrete caused by the aggressive external environment is one of the main problems that can reduce the durability of buildings. The paper analyzes the influence of the type of component on selected properties of lightweight concrete (LWC) exposed to aggressive liquids. When lightweight concrete containing porous aggregates is used, the influence of an aggressive environment may be of particular...
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Interactions in aqueous solutions of K-peptide and DMSO – spectroscopic and calorimetric studies
PublicationIntroduction K-peptide (GILQINSRW) – short 9 amino acid fragment of the hen egg white lysozyme has the ability to form amyloid structures. Dimethyl sulfoxide (DMSO) is an osmolyte which can alter this ability. Our goal was to get an insight into the mechanism of Kpeptide-DMSO interactions in aqueous solutions. Such a knowledge can be helpful to understand processes leading to various neurodegenerative diseases. Methods ATR-FTIR...
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Intramolecular Proton Transfer in the Radical Anion of Cytidine Monophosphate Sheds Light on the Sensitivities of Dry vs Wet DNA to Electron Attachment-Induced Damage
PublicationSingle-strand breaks (SSBs) induced via electron attachment were previously observed in dry DNA under ultrahigh vacuum (UHV), while hydrated electrons were found not able to induce this DNA damage in an aqueous solution. To explain these findings, crossed electron-molecular beam (CEMB) and anion photoelectron spectroscopy (aPES) experiments coupled to density functional theory (DFT) modeling were used to demonstrate the fundamental...
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Electrochemical detection of bacterial endotoxin lipopolysaccharide (LPS) on gold electrode modified with DAL-PEG-DK5-PEG-OH - Antimicrobial peptide conjugate
PublicationThis work describes fabrication of gold electrodes modified with peptide conjugate DAL-PEG-DK5-PEG-OH that enables ultra-sensitive detection of lipopolysaccharide (LPS) isolated from the reference strain of Escherichia coli O26:B6. The initial step of the established procedure implies immobilization of the fully protected DAL-PEG-DK5-PEG-OH peptide on the surface of the gold electrode previously modified by cysteamine. Then side...
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Improving operating efficiency of a gas turboset via cooperation with an absorption refrigerating machine
PublicationThe analysis of increase of ambient air temperature entering the compressor on reduction in power output from the turbine and increase fuel use was conduced. For medium size gas turbine operates in winter and summer conditions elementary power and economical values was calculated. Conditions of the determination of turbine inlet air cooling solution (using thermal storage for reduce equipment size) are presented
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Dempster-shafer theory-based trust and selfishness evaluation in mobile ad hoc networks
PublicationThe paper addresses the problem of selfishness detec-tion in mobile ad hoc networks. It describes an approach based on Dempster-Shafer theory of evidence. Special attention is paid to trust evaluation and using it as a metric for coping with (weighted) recommendations from third-party nodes. Efficiency and robustness of the pre-sented solution is discussed with an emphasis on resil-iency to false recommendations.
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Pharmaceutical applications of surfactants
PublicationIn this study we focused on biological activity of various surfactants. According to our research, they con act both as carriers as well as therapeutic agents. Depending on their concentration, they can create different structures in a solution, which influence their properties. Liposomes have a significant role in drug delivery system. Surfactants in from of bilayer are analogous to natural biological cell membrane.
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CAES – Energy storage providing stability for national power system
PublicationThis paper presents a short characteristics of the power system. It also describes various types of energy storage technologies. The suggested solution of accumulation and generation of electric power is based on the cooperation of gas turbine with Compressed Air Storage Energy systems – CAES. This analysis describes also various types of cooperation of CAES and renewable sources of energy, particularly wind power systems.
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Assessment of tensile forces in Sopot Forest Opera membrane by in situ measurements and iterative numerical strategy for inverse problem
PublicationAssessment of tensile forces in newly build Sopot Forest Opera roofing membrane is presented. The procedure is based on in situ measurements and solution of the inverse problem by an iterative procedure. The goal of the analysis is to determine whether the stress state of the membrane is consistent with the design assumptions. The paper contains the description of measurements, used instruments, applied loadings, numerical investiga-tions...
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Design and implementation principles of FIReWORK ONLINE - the VHDL autogenerator for hardware structures
PublicationThe paper presents an aspects of remote autogeneration of hardware structures. The solution is an online application, that is running on the server side and allows to design a particular filters and other selected hardware and generate its structure in the form of VHDL, dedicated to FPGA design environments. The paper also addresses the problem of parameterization of algorithms used to generate the hardware structures and current...
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History-based dynamic weight voting for multi-agent systems
PublicationTaking decision in multi-agent systems may involve voting. Two basic voting protocols are surveyed in the paper. Then, a new history-based dynamic weight voting is proposed. This voting protocol allows for identification of the agents which contribute to the correct system decision. The proposed solution is contrasted with majority voting and with weighted average voting, to show its advantages
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Enhancing Performance of Switched Parasitic Antenna for Localization in Wireless Sensor Networks
PublicationThis paper presents an Electronically Steerable Parasitic Array Radiator (ESPAR) antenna with enhanced performance of estimating the incoming signal direction. Designed antenna is dedicated for 2.4 GHz ISM applications with emphasis on Wireless Sensor Networks (WSN). The limitations of the existing design approach are illustrated, as well as perspectives and challenges of the proposed solution in relation to the localization in...
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Novel single-stage buck-boost inverter with unfolding circuit
PublicationA novel solution of a single-stage buck-boost inverter with unfolding circuit at the output stage is presented. The inverter has a wide range of input voltage regulation, minimum passive components and a very flexible control structure. It can be applied for renewable energy systems where high power density is required. Our simulation results confirmed all theoretical statements
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Wideband Radio Direction Finder Implemented in Software Defined Radio Technology
PublicationIn the paper a wideband radio direction finder (RDF) implemented in software defined radio (SDR) technology and the results of hardware layer research, including developed antenna switching unit (ASU), are presented. The results of tests of the devices, which are the part of the software defined radio platform (SDRP), and antenna switching unit, confirmed the possibility of using selected components in the final solution.
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Emergency condition of the ceramic facade of a residential building
PublicationThe paper presents a description of the technical condition of the ceramic cladding of a residential building, the technical condition of which deteriorated significantly after only a few years of operation. The analysis of the influence of the applied design and working solutions on the façade failure frequency was analyzed. The article presents a conceptual solution to bring the building to the proper technical condition in terms...
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Emergency condition of the ceramic facade of a residential building
PublicationThe paper presents a description of the technical condition of the ceramic cladding of a residential building, the technical condition of which deteriorated significantly after only a few years of operation. The analysis of the influence of the applied design and working solutions on the façade failure frequency was analyzed. The article presents a conceptual solution to bring the building to the proper technical condition in terms...
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On Solvability of Boundary Value Problems for Elastic Micropolar Shells with Rigid Inclusions
PublicationIn the framework of the linear theory of micropolar shells, existence and uniqueness theorems for weak solutions of boundary value problems describing small deformations of elastic micropolar shells connected to a system of absolutely rigid bodies are proved. The definition of a weak solution is based on the principle of virial movements. A feature of this problem is non-standard boundary conditions at the interface between the...
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A reactive algorithm for deducing nodal forwarding behavior in a multihop ad-hoc wireless network in the presence of errors
PublicationA novel algorithm is presented to deduce individual nodal forwarding behavior from standard end-to-end acknowledgments. The algorithm is based on a well-established mathematical method and is robust to network related errors and nodal behavior changes. The proposed solution was verified in a network simulation, during which it achieved sound results in a challenging multihop ad-hoc network environment.
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Modelowanie przepływu ustalonego niejednostajnego w sieciach kanałów otwartych z uwzględnieniem obiektów hydrotechnicznych
PublicationW pracy sformułowano zagadnienie brzegowe dla równania energii opisującego przepływ ustalony niejednostajny i przedstawiono sposób jego rozwiązania przy pomocy metody różnicowej. Zaproponowana metoda obliczeń nadaje się do analizy przepływu w dendrycznych i pierścieniowych sieciach kanałów otwartych. Ponadto na przykładzie przelewu prostokątnego zaproponowano metodę uwzględnienia w obliczeniach zabudowy hydrotechnicznej. Słowa...
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ANALYSIS OF ROLLING RESISTANCE OF TIRES WITH RUN FLAT INSERT APPLYING DRUM METHOD AND RADIAL CHARACTERISTIC
PublicationThis paper presents analysis of rolling resistance of tires with RUN FLAT insert applying drum method and radial characteristic. The conducted studies indicated changes in operational properties of wheel, occurring as a result of inflation pressure drop in the wheel. As regards radial elasticity, such changes result in significant drop of radial rigidity and increase of static deflection and increase of tire rolling resistance....
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Research on operational characteristics of tyres with run flat insert
PublicationThe paper describes results of research on heavy vehicle tyre with Run Flat VFI insert. The experiment has included the determination of heat generation, rolling resistanceand radial stifnessof two different tyre designes (textile and steel carcass). The results have been used for the purpose of ewalution of tyre operating characteristics. The study included research on non-inflated tyre properties. The purpose of the paper is...
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Experimental and Numerical Investigations of the Effect of Curing Conditions on the Temperature Rise of Concrete
PublicationThis paper presents experimental and numerical studies investigating the impact of three curing conditions on temperature evolution in concrete cubes. The tests were performed on samples of the same volume (3.375 dm3) under different curing conditions: room temperature, insulation boxes, and adiabatic calorimeter. Various cements (Portland cement, Portland composite cement, and blast furnace slag cement) and aggregates (gravel...
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Modeling the Influence of Salts on the Critical Micelle Concentration of Ionic Surfactants
PublicationWe show for the first time that a phenomenological, augmented volume-based thermodynamics (aVBT) model is capable to predict the critical micelle concentrations of ionic surfactants, including ionic liquids, with added salts. The model also adjusts for the type of salt added by including its molecular volume, which might form a connection to the Hofmeister effect. The other physico-chemically relevant quantities included in the...
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Wear of Ultra-thin DLC or Tungsten-modified DLC Coatings under Reciprocating Sliding
PublicationIn the paper results are presented from tests in reciprocating sliding of self mated specimens of DLC and tungsten modified DLC coatings on stainless steel substrate. The contact geometry chosen for the research task was ball on flat. The contacts were lubricated either with distilled water or medical saline solution. Results are presented with regard to wear resistance as a function of material type and lubricant used.
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Usefulness of the voltamperometric method for assessment of the purity of soil
PublicationThis paper presents a voltammetric analysis of soil. It shows that the voltammetry is a useful method for the assessment of soil contaminated with heavy metal ions. There are two major problems with voltammetry analysis: the diffusion coefficient and the measurement system. The paper contains a short literature study of mathematical equations and a study of differences between soil and water measurements. Suggestions of the solution...
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Trolleybuses with traction batteries for autonomous running
PublicationIn 2009 the transport company of city Gdynia (Poland) introducet in the operation trolleybuses fitted with traction batteries. This solution was designed for emergency situations, such as: damage of overhead lines or power loss. Transport company also considering the use of batteries in regular use. The article presents the operational experiences gained during the current operation. Furthermore, there are presented new trends...
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Adaption of Open Science Paradigm at Gdańsk University of Technology
PublicationThe paper describes the basic principles standing behind Open Access and will try to dispel the doubts behind them. Further the solution adapted by the Gdańsk University of Technology is presented. Later on the systems that the University uses and means of their integration into a complex Open Science platform are described. Finally the procedures needed to publish a document in the repository alongside the University's policy...
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Bacteriophages as an antistaphylococcal agent
PublicationRecently observed increase of infection caused by Staphylococcus aureus is currently one of the most important problem of clinical microbiology. Most of the strains responsible for the infections are a MRSA (methicillin resistant Staphylococcus aureus) strains. In this situation commonly used antibiotics are not sufficient. There is an urgent need to search for a new nonatibiotic treatment against this pathogen. In the literature...
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Trolleybus with traction batteries for autonomous running
PublicationIn 2009 the transport company of city Gdynia (Poland) introduced in the operation trolleybuses fitted with traction batteries. This solution was designed for emergency situations, such as: damage of overhead lines or power loss. Transport company also considering the use of batteries in regular use. The article presents the operational experiences gained during the current operation. Furthermore, there are presented new trends...
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Elastic distortional buckling of thin-walled bars of closed quadratic cross-section
PublicationIn this study a tin-walled bar with closed quadratic cross-section is considered. The elastic stability of axially compressed bar related to the cross-section distortion is investigated. The governing differential equatio is derived with aid of the principle of stationary potential energy. The critical load for simply supported bar is found in an analytical form and it is copared with the FEM solution. Sufficient accuracy of the...
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A note on an approximative scheme of finding almost homoclinic solutions for Newtonian systems
PublicationIn this work we will be concerned with the existence of an almost homoclinic solution for a perturbed Newtonian system in a finite dimensional space. It is assumed that a potential is C^1 smooth and its gradient is bounded with respect to a time variable. Moreover, a forcing term is continuous, bounded and squere integrable. We will show that the appproximative scheme due to J. Janczewska for a time periodic potential extends to...
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Elastic distortional buckling of thin-walled bars of closed quadratic cross-section
PublicationIn this study a thin-walled bar with closed quadratic cross-section is considered. The elastic stability of axially compressed bar related to the cross-section distortion is investigated. The governing differential equation is derived with aid of the principle of stationary total potential energy. The critical load for the simply supported bar is found in analytical form and it is compared with the FEM solution. Sufficient accuracy...
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Revalorisation of Modernist and Social Modernist Interiors in Gdynia
PublicationIn the 1920s and 1930s, elaborate designing of prestigious interiors of public buildings, shops or tenement houses was important challenge for every architect who respected theri work. Apart from creating, at the design decor, the designers usually made sure that their concept was executed in every single detail. Only an overall aestetic solution could form a complete picture of a unique pieceod architecture.
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Monitoring wizyjny w systemach zabezpieczenia transportu wodnego. Koncepcja implementacyjna
PublicationW artykule autorzy przedstawiają koncepcję zastosowania własnych badań nad pomiarem prędkości przepływu cieczy do zastosowań praktycznych w pomiarach przepływu wody w kanałach otwartych i rzekach. Jako narzędzie pomiarowe wykorzystują zestaw aparatów synchronicznych, które rejestrują indykatory przepływu znajdujące się na powierzchni analizowanej cieczy. Aparat matematyczny przedstawiony w rozwiązaniu sprowadza się do stosowania...
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Inżynieria odwrotna bazy paliw płynnych w Gdańsku
PublicationArtykuł prezentuje prace z zakresu pozyskania danych o zbiornikach bazy paliw płynnych w Gdańsku. Przedstawione rozwiązanie nie ogranicza się tylko do stworzenia (rejestracji) chmury punktów, ale jest próbą wskazania użycia naziemnego skaningu laserowego do stworzenia bazy informacji o bazie paliw – w tym głównie geometrii zbiorników. Autorzy prezentują proces inwentaryzacji, rejestrację chmury punktów oraz wskazują zasady tworzenia...
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Multistatyczny, Dopplerowski System określania położenia i prędkości ruchomych celów w wodzie
PublicationW omawianym w pracy multistatycznym, dopplerowskim systemie określania położenia i prędkości ruchomych celów w wodzie źródłem sygnału są dwa nadajniki emitujące sinusoidalne, akustyczne fale ciągłe o różnych częstotliwościach, które po odbiciu od ruchomego celu są obierane przez cztery hydrofony. W artykule przedstawiono analize teoretyczna efektu Dopplera, na którym oparte jest działanie systemu oraz metodę rozwiązania głównych...
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Wodór jako paliwo cz. 1
PublicationW artykule przedstawiono wodór jako nowoczesny nośnik energii oraz jego zastosowanie techniczne w ujęciu konwersji energii. Przybliżono jego odkrycie, właściwości oraz jego wykorzystanie od odkrycia do współczesności. Dokonano opisu budowy i zasady działania ogniw paliwowych. Omówiono ich podział przedstawiając zalety i wady każdego rozwiązania oraz ich zastosowanie techniczne w zależności od typu ogniwa.
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A CMOS Pixel With Embedded ADC, Digital CDS and Gain Correction Capability for Massively Parallel Imaging Array
PublicationIn the paper, a CMOS pixel has been proposed for imaging arrays with massively parallel image acquisition and simultaneous compensation of dark signal nonuniformity (DSNU) as well as photoresponse nonuniformity (PRNU). In our solution the pixel contains all necessary functional blocks: a photosensor and an analog-to-digital converter (ADC) with built-in correlated double sampling (CDS) integrated together. It is implemented in...
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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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Investigation of vortex assisted magnetic deep eutectic solvent based dispersive liquid–liquid microextraction for separation and determination of vanadium from water and food matrices: Multivariate analysis
PublicationA new and simple vortex assisted magnetic deep eutectic solvent dispersive liquid–liquid microextraction procedure (VA-MDES-DLLME) was developed for the determination of vanadium (V) in food and water samples by flame atomic absorption spectrometry (FAAS). In the extraction medium, a bis(acetylpivalylmethane) ethylenediimine (H2APM2en) was used for the complexation of V(V) in sample solution at pH 6. The VA-MDES-DLLME was optimized...
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Metrisable assessment of the course of stream‑systemic processes in vector form in industry 4.0
PublicationThe goal of this paper is to present an innovative conception how to use metrisable vector structure of a manufacturing process, based on quantitative relations between the activity of input streams, features of the product, and effect of losses; all of which are excellent practical solution for Industry 4.0, and in turn intelligent factories. This solution can be a usefull way in the process of building sustainable organization....
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Non-standard contact conditions in generalized continua: microblock contact model for a Cosserat body
PublicationGeneralized continuum theories involve non-standard boundary conditions that are associated with the additional kinematic variables introduced in those theories, e.g., higher gradients of the displacement field or additional kinematic degrees of freedom. Accordingly, formulation of a contact problem for such a continuum necessarily requires that adequate contact conditions are formulated for the additional kinematic variables and/or...
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Disaster-Resilient Routing Schemes for Regional Failures
PublicationLarge-scale natural disasters can have a profound effect on the telecommunication services in the affected geographical area. Hence, it is important to develop routing approaches that may help in circumventing damaged regional areas of a network. This prompted the development of geographically diverse routing schemes and also of disaster-risk aware routing schemes. A minimum-cost geodiverse routing, where a minimum geographical...
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Analysis of Rolling Resistance of Tires With Run Flat Insert
PublicationRun flat properties are required for tires intended for special applications like military or rescue vehicles. Run-Flat inserts make possible to drive a car or truck, with certain restrictions, also when inflation pressure is very low or non-existing (after tire damage). Rolling resistance of tires rolling the inserts increases considerably in relation to the rolling resistance of properly inflated tires. This paper presents results...
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Subadditivity of the minimum output entropy and superactivation of the classical capacity of quantum multiple access channels
PublicationWe study subadditivity of the minimum output entropy (Hmin) of quantum multiple access channels (MACs). We provide an example of violation of the additivity theorem for Hmin known in classical information theory. Our result is based on a fundamental property of MACs, i.e., independence of each sender. The channels used in the example can be constructed explicitly. On the basis of subadditivity of Hmin we also provide an example...
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Imitating Quantum Probabilities: Beyond Bell’s Theorem and Tsirelson Bounds
PublicationLocal hidden-variable model of singlet-state correlations discussed in M. Czachor, Acta Phys. Polon. A 139, 70, is shown to be a particular case of an infinite hierarchy of local hidden-variable models based on an infinite hierarchy of calculi. Violation of Bell-type inequalities can be interpreted as a `confusion of languages' problem, a result of mixing different but neighboring levels of the hierarchy. Mixing of non-neighboring...
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KASKADA Platform in Cloud Environment
PublicationKASKADA is a computing platform for developing and running services and applications oriented to multimedia processing and data streaming. A solution for serving the platform in the PaaS model is presented. The paper briefly describes the software for creating the private cloud environment based on the OpenStack software. The coud has been deployed to a supercomputer working in C2 NIWA at the Gdansk University of technology. This...