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Wyniki wyszukiwania dla: FLEXIBLE POLYURETHANE FOAMS
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Micro-Raman spectroscopy in the studies of multiphase separated polyurethanes. [online] W: [Proc.] UTECH Europe 2003 . The International Polyurethane Industry Conference and Exhibition. 25/26/27 March 2003, The Hague, Netherlands. London: Crain Communications Ltd. Dostępny w World Wide Web: http://UTECH-2003.com + wydruk.**2003 [s. 123-130 bibliogr. 41 poz.]Mikro-Ramanowska spektroskopia w badaniach poliuretanów wykazujących separację wielofazową.
PublikacjaPrzedmiotem badań były trzy próbki poliuretanowe o zawartości 30% segmentówsztywnych otrzymanych z politlenku propylenu, diizocyjanianu difenylometanui butanodiolu. Próbki te wykazują morfologię wielofazową, w której można wy-różnić globule i sferolity rozproszone w matrycy polimerowej.Za pomocą spek-troskopii mikro-Ramana przeprowadzono mikroanalizę chemiczną wszystkich ele-mentów morfologicznych. Stwierdzono odmienny skład...
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3D porous graphene-based structures- synthesis and applications
PublikacjaPorous carbon-based materials are of the great industrial and academic interest due to their high surface area, low density, good electrical conductivity, chemical inertness and low cost of fabrication. Up to now, the main approach to obtain porous carbon structures has involved the pyrolysis of carbonaceous natural or synthetic precursors. After the isolation of graphene, the interest in 3D porous graphene-based structures (called...
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EVALUATION OF THE EFFICIENCY OF FLEXICURITY IMPLEMENTATION IN OECD COUNTRIES
PublikacjaFlexicurity is a policy of flexible and secure labour market. It has been the subject of many analyses, however, a coherent evaluation methodology is difficult to specify. The purpose of this paper is to propose a Data Envelopment Analysis based model for the evaluation of the efficiency of flexicurity implementation in OECD countries. The results will be used to create the ranking of countries, to determine changes in time, and...
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The changes of crosslink density of polyurethanes synthesised with using recycled component. Chemical structure and mechanical properties investigations.
PublikacjaThis paper aims at the utilisation of glycerolysate (Gly) obtained in polyurethane recycling process by means of crude glycerine, which has in its structure hydroxyl end groups that allow for further processing. Polyurethanes (PUs) were synthesised using prepolymer method with the mixture of neat polyol and glycerolysate, in different ratios, with 4,4-diphenylmethane diisocyanate (MDI). The prepolymer was subsequently extended...
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GRAPHENE-BASED SUPERCAPACITORS APPLICATION FOR ENERGY STORAGE
PublikacjaRecent advances in graphene-based supercapacitor technology for energy storage application were summarized. The comparison of different types of electrode materials in such supercapacitors was performed. The supercapacitors with graphene-based electrodes exhibit outstanding performance: high charge-discharge rate, high power density, high energy density and long cycle-life, what makes them suitable for various applications, e.g....
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Mashup Approaches for Improving Service Oriented Business Scenarios
PublikacjaTwo kinds of business scenarios are considered: application- and service-oriented. It is shown that the former are more flexible and easier reconfigurable for both traditional (human-oriented) and IT services. Moreover, complex IT services can be created by simple IT services using the modern mashup technology. It is the reason why such business scenarios can be modeled by BPMN in much easier ways. A simple example of a supply...
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Environmental impact and industrial development of biorenewable resources for polyurethanes
PublikacjaPolyurethanes are among the most developed types of polymers. They are produced from the three primary components, i.e., polyols, low-molecular-weight glycols used as chain extenders, and diisocyanates. Until recently, all these substrates have been obtained via petrochemical processes. A decrease in petroleum-based resources and new ecological trends in chemistry, chemical technology, and materials engineering have generated increasing...
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Application of Open-Hardware-Based Solutions for Rapid Transition From Stationary to the Remote Teaching Model During Pandemic
PublikacjaWhile research indicates usefulness of remote laboratories in teaching of digital hardware systems, their main application is to complement stationary classes. This work presents a low-cost, scalable architecture that supports rapid transformation of teaching to a model based solely on remote access mechanisms. Background: Adaptation of online laboratory solutions from the literature to en-masse teaching of digital circuits is...
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Molecular hydrogen solvated in water – A computational study
PublikacjaThe aqueous hydrogen molecule is studied with molecular dynamics simulations at ambient temperature and pressure conditions, using a newly developed flexible and polarizable H2 molecule model. The design and implementation of this model, compatible with an existing flexible and polarizable force field for water, is presented in detail. The structure of the hydration layer suggests that first-shell water molecules accommodate the...
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SVC and power transformers controllers coordination
PublikacjaThe use of shunt compensators such as FACTS (for example SVC) in power systems gives possibility of fast and flexible control of voltage or reactive power. An efficient cooperation between a transformer and compensator connected to busbars, or transformer’s tertiary winding, requires a proper coordination of controls. The article contains theoretical considerations and simulation results which indicate that such co-ordination is...
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High Speed Milling vibration surveillance with optimal spindle speed based on optimal speeds map
PublikacjaThe paper presents the method of the surveillance of the self-excited chatter vibration. At first, the workpiece modal parameters are estimated based on experimental data which leads to verification of computational model. Then, for selected surface points optimal spindle speeds are calculated. By considering sufficient amount of points it is possible to build a map of optimal spindle speeds. Experimental results show that this...
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Gas turbines – technological development and potential use in CAES systems
PublikacjaThis article briefly describes Compressed Air Energy Storage (CAES), focusing on the technological development of one of the key elements of such systems – the gas turbines. It presents the basic parameters and features of gas turbines, as well as turbine classes with example models. Main tendencies in the structural and technological development are discussed. Changes and trends on electric energy markets are becoming more and...
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Optimization of clamping stiffness during milling of high-dimensional structures with the use of techniques of experiment – aided virtual prototyping
PublikacjaThe subject of this paper is a method of searching for conditions of minimizing the vibration level of a tool-high dimensional flexible workpiece, at unchangeable technological parameters of the machining process. It depends on repeatable change of the values of the stiffness coefficients as soon as an optimal vibration state of the workpiece approaches. There are assessed the values of dominant ”peaks” in the frequency spectra...
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Effets de variabilite d'adhesion et de viellissement en collage structural
PublikacjaDivers essais peuvent etre employes afin d'evaluer la resistance a la fracture des joints adhesifes. Generalement, ces essais sont symetriques: les substrats sont identiques. Nous avons utilise une version asymetrique, ou un adherend flexible est colle a aderend rigide. Nous discutons ici du comportement d'un joint d'adhesion variable. Des resultats assez surprenants font le sujet prinicpal de cet article.
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Human voice modification using instantaneous complex frequency
PublikacjaThe paper presents the possibilities of changing human voice by modifying instantaneous complex frequency (ICF) of the speech signal. The proposed method provides a flexible way of altering voice without the necessity of finding fundamental frequency and formants' positions or detecting voiced and unvoiced fragments of speech. The algorithm is simple and fast. Apart from ICF it uses signal factorization into two factors: one fully...
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Ontology Oriented Approach to Service Selection and Invocation in Complex Context Analysis
PublikacjaContext-aware applications running in the intelligent space are taken into account and their execution in the service oriented environment is considered. It has been presented where and how SOA services can be utilized during their execution: to analyze current context of the application and to support execution of strictly determined actions suitable for that context. The proposed mechanism of context-aware service selection and...
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Data-driven models for fault detection using kernel pca:a water distribution system case study
PublikacjaKernel Principal Component Analysis (KPCA), an example of machine learning, can be considered a non-linear extension of the PCA method. While various applications of KPCA are known, this paper explores the possibility to use it for building a data-driven model of a non-linear system-the water distribution system of the Chojnice town (Poland). This model is utilised for fault detection with the emphasis on water leakage detection....
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Simulation of Parallel Applications on Large-scale Distributed Systems
PublikacjaThis chapter has a form of a review article in the field of simulating High-Performance Computing systems. We justify the need for a new versatile simulator considering heterogeneity, energy efficiency and reliability of HPC systems. We sketch the problems that need to be solved by such simulator and rationalize using discrete-event simulation for this purpose. Based on a review of existing discrete-event HPC simulation solutions...
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Styrene Oxidation by Copper(II) Complexes Salen-Type Encapsulated into Nay Zeolite
PublikacjaThe copper(II) complex with a Schiff-base salen-type ligand has been encapsulated in the nanopores of a NaY zeolite by using two different methodologies, the flexible ligand and in situ complex preparation methods. The encapsulated and non-encapsulated copper(II) complexes were screened as catalysts for styrene oxidation by using TBHP as the oxygen source in acetonitrile solvent. Under the optimized conditions, the catalysts exhibited...
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Earthquake–induced pounding on response of adjacent structures in series: experimental and numerical study
PublikacjaPounding between structures in series during earthquakes may cause serious damage in the structur-al elements. The aim of this paper is to show the results of an experimental and numerical study that is focused on pounding between more than two structures which may be called "structures in series". In this study, the shaking table experiments, as well as the numerical analyses, were performed using three tower models including...
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Structure-based design and evaluation of novel N-phenyl-1H-indol-2-amine derivatives for fat mass and obesity-associated (FTO) protein inhibition
PublikacjaFat mass and obesity-associated (FTO) protein contributes to non-syndromic human obesity which refers to excessive fat accumulation in human body and results in health risk. FTO protein has become a promising target for anti-obesity medicines as there is an immense need for the rational design of potent inhibitors to treat obesity. In our study, a new scaffold N-phenyl-1H-indol-2-amine was selected as a base for FTO protein inhibitors...
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Radio Channel Measurements in Off-Body Communications in a Ferry Passenger Cabin
PublikacjaThis paper presents an off-body radio channel measurements in a ferry passenger cabin at 2.45 GHz band, for static sleeping scenarios with different body orientation and on-body antennas placements, and also for upper and lower sleeping berths. The measurements have been performed with two types of on-body wearable receiving antennas: FlexPIFA (flexible planar inverted F antenna), and FlexNotch (flexible adhesive-backed notch antenna)...
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Improving flexibility and performance of PVM applications by distributed partial evaluation
PublikacjaA new framework for developing both flexible and efficient PVM applications is described. We propose Architecture Templates Interface (ATI) that allows to control application granularity and parallelism. To ensure high application efficiency we extend partial evaluation strategy into domain of distributed applications obtaining Distributed Partial Evaluation (DPE). Both ATI and DPE were implemented using a new distributed programming...
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The Urbanity Phenomenon – Tradition and New Cultural Iterations
PublikacjaCities that have managed to survive and rebuild lost urbanity do not close themselves towards new forms that are largely generated by culture. People are increasingly organized around common, local goals. They want to live in cities that open themselves up to differences, with culture as a tool for the revitalization of urbanity. Flexible management methods, tailored to the context and new needs, are therefore emphasized. Nowadays,...
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Processing of Polyester-Urethane Filament and Characterization of FFF 3D Printed Elastic Porous Structures with Potential in Cancellous Bone Tissue Engineering
PublikacjaThis paper addresses the potential of self-made polyester-urethane filament as a candidate for Fused Filament Fabrication (FFF)-based 3D printing (3DP) in medical applications. Since the industry does not provide many ready-made solutions of medical-grade polyurethane filaments, we undertook research aimed at presenting the process of thermoplastic polyurethane (TPU) filament formation, detailed characteristics, and 3DP of specially...
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Polyurethanes for Coating, Adhesives, and Other Applications
PublikacjaAn interesting group of polyurethane (PU) materials are coatings, adhesives, sealants, and thickeners. A wide base of raw materials and various methods of PU synthesis allows production of materials with a wide range of properties that can be commonly used in many industries. This chapter describes the main types of PU coatings and adhesives and special application PUs and the methods of their production. The materials described...
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Terminal charging scheduling of battery electric buses based on vehicle routing problem
PublikacjaElectric buses are considered to be a viable solution for reducing emission in dense urban areas. However, the greater charging time is a huge challenge for operators. In this paper, charging scheduling method was elaborated based on vehicle routing problem using mixed-integer linear programming model. The main novelty of the paper is the combination of modelling aspect, namely flexible turn sequence and heterogeneous shared charging...
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Lightweight structures in architecture: scenarios for the future
PublikacjaLightweight structures - structures with a reduced weight, which otherwise retain the qualities necessary for the building performance, ensuring a proper durability and strength, safety, indoor environmental quality and energy efficiency; stuctures which strive for the optimization of structural systems - are in tune with current trends and socio-economic, environmental and technological factors. The growing interest in the lightweight...
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Optimization of Single-Sided Lapping Kinematics Based on Statistical Analysis of Abrasive Particles Trajectories
PublikacjaThe chapter presents the influence of selected kinematic parameters on the geometrical results of the single-sided lapping process. The optimization of these parameters is aimed at improving the quality and flatness of the machined surfaces. The uniformity of tool wear was assumed as main optimization criterion. Lapping plate wear model was created and in detail was analyzed. A Matlab program was designed to simulate the abrasive...
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Beam on elastic foundation with anticlastic curvature: Application to analysis of mode I fracture tests
PublikacjaA first order correction is proposed taking into account both interface elasticity and transverse anticlastic curvature of flexible substrate(s) in the DCB (and related tests). Adherends are represented by Kirchhoff-Love plates, and the interface by Winkler-type elastic foundation. Two functions are introduced, representing evolution of beam deflection along the sample midline and anticlastic curvature along the plate. A method...
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Efficient Finite Element Analysis of Axially Symmetrical Waveguides and Waveguide Discontinuities
PublikacjaA combination of the body-of-revolution and finite element methods is adopted for full-wave analysis of waveguides and waveguide discontinuities involving angular field variation. Such an approach is highly efficient and much more flexible than analytical techniques. The method is performed in two different cases: utilizing a generalized impedance matrix to determine the scattering parameters of a single waveguide section and utilizing...
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Polyisocyanates from Sustainable Resources
PublikacjaIsocyanates, next to polyols, constitute the major components essential for polyurethane (PU) production. They have a significant impact on physicochemical, mechanical, and thermal properties of PU materials. They also have an impact on those materials’ purposes, forms, textures, and other features. The available and used isocyanates are of a petrochemical origin. With the development of a trend toward green chemistry in the science...
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Complex Root Finding Algorithm Based on Delaunay Triangulation
PublikacjaA simple and flexible algorithm for finding zeros of a complex function is presented. An arbitrary-shaped search region can be considered and a very wide class of functions can be analyzed, including those containing singular points or even branch cuts. The proposed technique is based on sampling the function at nodes of a regular or a self-adaptive mesh and on the analysis of the function sign changes. As a result, a set of candidate points...
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Microplastics removal from aqueous environment by metal organic frameworks
PublikacjaThis paper provides an overview of recent research performed on the applications of metal–organic frameworks (MOFs) for microplastics (MPs) removal from aqueous environments. MPs pollution has become a major environmental concern due to its negative impacts on aquatic ecosystems and human health. Therefore, developing effective and sustainable methods for removing them from aqueous environments is crucial. In recent years, MOFs...
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Two-step Conversion of Crude Glycerol Generated by Biodiesel Production into Biopolyols: Synthesis, Structural and Physical Chemical Characterization
PublikacjaIn this work biopolyols were synthesized via two-step process from crude glycerol and castor oil. For better evaluation of analyzed process, the impact of its time and temperature on the structure and properties of biopolyols was determined. Obtained results fully justified conducting of synthesis in two steps. Prepared materials were characterized by hydroxyl value and water content comparable to polyols industrially applied in...
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Renewable natural resources as green alternative substrates to obtain bio-based non-isocyanate polyurethanes-review
PublikacjaCommercially available polyurethanes are synthesized by the polyaddition of diisocyanates with polyols and low molecular weight chain extenders. A new approach to polyurethanes synthesis is realized via non-isocyanate routes. Negative impacts of petroleum-based chemicals on the environment and human health as well as gradual reduction of fuel-based resources, which leads to an increase in their prices, are an incentive to looking...
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Thermal and Mechanical Properties of Microporous Polyurethanes Modified with Reduced Graphene Oxide
PublikacjaMicroporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide (RGO). The materials were prepared without solvent via in situ polymerization. From a technological point of view, it is very important to obtain functional materials by using reacting compounds only. The thermal characteristics of obtained MPU were investigated using TGA, DSC, and DMA techniques. In comparison to nonmodified microporous...
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Thermal and mechanical properties of polyurethanes modified with L-ascorbic acid
PublikacjaIn this study we report the thermal and mechanical properties of polyurethanes modified with ascorbic acid (AA). Ascorbic acid was used as a modifier at concentration of 1 or 2 mass%. The antioxidative properties of AA may improve the biocompatibility of the obtained materials, which were designed for biomedical applications. In this paper we describe characterization of obtained unmodified and ascorbic acid modified polyurethanes...
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A Simple Replica Method as the Way to Obtain a Morphologically and Mechanically Bone-like Iron-Based Biodegradable Material
PublikacjaPorous iron-based scaffolds were prepared by the simple replica method using polyurethane foam as a template and applying the sintering process in a tube furnace. Their surface morphology was characterized using scanning electron microscopy (SEM) and phase homogeneity was confirmed using X-ray diffraction (XRD). Corrosion behavior was determined using immersion and potentiodynamic polarization methods in phosphate buffered saline...
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Global Complex Roots and Poles Finding Algorithm Based on Phase Analysis for Propagation and Radiation Problems
PublikacjaA flexible and effective algorithm for complex roots and poles finding is presented. A wide class of analytic functions can be analyzed, and any arbitrarily shaped search region can be considered. The method is very simple and intuitive. It is based on sampling a function at the nodes of a regular mesh, and on the analysis of the function phase. As a result, a set of candidate regions is created and then the roots/poles are verified...
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Winding function approach based design of novel five-phase brushless doubly fed induction generator
PublikacjaThe paper presents the concept of the new design of the five-phase brushless doubly fed induction generator. The generator is dedicated to the modern wind turbine. The innovative design approach uses a five-phase power supply from the stator control winding side of the generator with a stator three-phase classic power winding. The research results presented indicate that the electromagnetic coupling between the control and power...
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Highly crystalline colloidal nickel oxide hole transport layer for low-temperature processable perovskite solar cell
PublikacjaHighly crystalline NiOX usually requires high annealing temperature (>300 °C) which is incompatible with flexible substrate and might consume high amount of energy. Herein, we demonstrate a facile emulsion process to synthesize highly crystalline, low temperature deposition (<150 °C) and solution processable NiOx nanoparticles (NPs) as a hole transport layer for the perovskite solar cells (PVSCs). A novel surfactant of tetramethylammonium...
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A decision-making system supporting selection of commanded outputs for a ship's propulsion system with a controllable pitch propeller
PublikacjaThe ship's operators have to make decisions regarding the values of commanded outputs (commanded engine speed and pitch ratio) which ensure maximum vessel speed and minimum fuel consumption. Obviously, the presented decision problems are opposed. Therefore, there is a need for a compromise solution that enables more flexible vessel voyage planning. This paper deals with development of a computer-aided system supporting selection...
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Report of Eurocode 7 application for pile foundation design in Poland
PublikacjaThe EC7 rules of geotechnical design are in use in Poland for several years, even though there is no National annex. With regard to pile foundations, there are valid EC7 recommendations concerning design approaches, load partial coefficients, correlation coefficients and capacity partial coefficients. Polish designers can be quite flexible when it comes to choose a method for static, bearing capacity and settlement calculations....
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Charge-assisted N(+)–H···(−)S hydrogen bonds in the crystal structure of selected diammonium thiophenolates.
PublikacjaNew salts of thiophenol with three flexible aliphatic diamines H2N(CH2)nNH2 (n = 2, 4 and 6) have been synthesized and characterized by elemental analyses, IR spectroscopy and X-ray crystallography in order to analyze their supramolecular architecture. Structural analyses indicate that in the crystals, proton transfer has occurred, with the –SH group giving (+)N–H···S(−) hydrogen bonding interaction. The structure of compound 1...
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Coplanar Waveguide Fed Ultra-Wideband Antenna Over the Planar and Cylindrical Surfaces
PublikacjaThe investigation of coplanar waveguide fed ultra-wideband antenna and the influence of the proximity of different materials on the reflection coefficients and radiation character-istics is presented. The antenna is composed of two circular coplanar strips which enclose slot aperture of similar shape and is designed on a thin and flexible substrate. From the modeling and experimental tests the antenna shows good performance in...
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Gaining knowledge through experience: developing decisional DNA applications in robotics
PublikacjaOmówiono nowatorskie podejscie do zastosowania wiedzy opartej na doświadczeniu i budowie decyzyjnego DNA w obszarach związanych z robotyką.In this article, we explore an approach that integrates Decisional DNA, a domain-independent, flexible, and standard knowledge representation structure, with robots in order to test the usability and suitability of this novel knowledge representation structure. Core issues in using this Decisional...
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TensorHive: Management of Exclusive GPU Access for Distributed Machine Learning Workloads
PublikacjaTensorHive is a tool for organizing work of research and engineering teams that use servers with GPUs for machine learning workloads. In a comprehensive web interface, it supports reservation of GPUs for exclusive usage, hardware monitoring, as well as configuring, executing and queuing distributed computational jobs. Focusing on easy installation and simple configuration, the tool automatically detects the available computing...
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublikacjaIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...
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Evaluation of Immobilization of Selected Peat-Isolated Yeast Strains of the Species Candida albicans and Candida subhashii on the Surface of Artificial Support Materials Used for Biotrickling Filtration
PublikacjaThe paper describes the process of n-butanol abatement by unicellular fungi, able to deplete n-butanol content in gas, by using n-butanol as source of carbon. Isolated and identified fungi species Candida albicans and Candida subhashii were subjected to a viability process via assimilation of carbon from hydrophilic and hydrophobic compounds. The isolates, which exhibited the ability to assimilate carbon, were immobilized on four...