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Radar technique in application of interlayer identification connections
PublicationOne of important issues in pavement construction is to ensure that layers applied directly one on top of the other make up a continuous whole and form an integral construction complex. An appropriate interlayer connection plays here significant role ensuring proper transmission of distortions generated by wheels of vehicles to lower layers and preventing water penetration between the layers. In case of damaged pavements where lack...
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Self-organized multilayered graphene-boron doped diamond hybrid nanowalls for high performance electron emission devices
PublicationCarbon nanomaterials like nanotubes, nanoflakes/nanowalls and graphene have been used as electron sources due to their superior field electron emission (FEE) characteristics. Nevertheless, these materials show poor stability and a short lifetime, preventing them from being used in practical device applications. The intention of this study was to find an innovative nanomaterial, possessing both high robustness and reliable FEE behavior....
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The dependence of linear viscoelasticity limits of cold-recycled mixtures on time of curing and compaction method
PublicationCold-recycled mixtures are currently among the most widely used and investigated methods that enable recycling of old pavement structures in an environmentally friendly manner. Upon milling, the old pavement structure – whose gradation can be improved with addition of virgin aggregate – is mixed and compacted at ambient temperature. The main binding agents are bituminous emulsion and cement. Due to their dual binding behaviour,...
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High frequency impulse ground penetrating radar application in assessment of interlayer connections
PublicationGround Penetrating Radar (GPR) technique is commonly used in the nondestructive evaluation of pavement structures. In particular, this method is used to estimate thicknesses of pavement layers as well as it can be utilized in advanced studies of pavement structures. The device presented in this paper comprise the high frequency impulse antennas that allow for investigating the interlayer zones in terms of their electromagnetic...
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Open-Source Coprocessor for Integer Multiple Precision Arithmetic
PublicationThis paper presents an open-source digital circuit of the coprocessor for an integer multiple-precision arithmetic (MPA). The purpose of this coprocessor is to support a central processing unit (CPU) by offloading computations requiring integer precision higher than 32/64 bits. The coprocessor is developed using the very high speed integrated circuit hardware description language (VHDL) as an intellectual property (IP) core. Therefore,...
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Investigation of low-temperature cracking in newly constructed high-modulus asphalt concrete base course of a motorway pavement
PublicationThe paper presents the issue of low-temperature transverse cracks which have developed in newly constructed base courses made of high-modulus asphalt concrete mix (HMAC). Numerous transverse cracks developed in the analysed HMAC base during the winter season before the pavement was actually completed, both at the transverse joint locations and in the areas between them. This had not happened so far on such a scale during road construction...
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Investigation of Performance and Configuration of a Selected IoT System—Middleware Deployment Benchmarking and Recommendations
PublicationNowadays Internet of Things is gaining more and more focus all over the world. As a concept it gives many opportunities for applications for society and it is expected that the number of software services deployed in this area will still grow fast. Especially important in this context are properties connected with deployment such as portability, scalability and balance between software requirements and hardware capabilities. In...
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Multi-core processing system for real-time image processing in embedded computer vision applications
PublicationW artykule opisano architekturę wielordzeniowego programowalnego systemu do przetwarzania obrazów w czasie rzeczywistym. Dane obrazu są przetwarzane równocześnie przez wszystkie procesory. System umożliwia niskopoziomowe przetwarzanie obrazów,np. odejmowanie tła, wykrywanie obiektów ruchomych, transformacje geometryczne, indeksowanie wykrytych obiektów, ocena ich kształtu oraz podstawowa analiza trajektorii ruchu. Ang:This paper...
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Performance assessment of OpenMP constructs and benchmarks using modern compilers and multi-core CPUs
PublicationConsidering ongoing developments of both modern CPUs, especially in the context of increasing numbers of cores, cache memory and architectures as well as compilers there is a constant need for benchmarking representative and frequently run workloads. The key metric is speed-up as the computational power of modern CPUs stems mainly from using multiple cores. In this paper, we show and discuss results from running codes such as:...
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The adiabatic potentials of low-lying electronic states of the NaRb molecule
PublicationAdiabatic potential energy curves and spectroscopic constants have been calculated for the NaRb molecule. The results of ten states of the symmetry Σ+, six states of the symmetry Π, and two states of the symmetry Δ are obtained by the nonrelativistic quantum chemical method used with pseudopotentials describing the interaction of valence electrons with atomic cores. Analysis is based on a comparison with the results of other theoretical...
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Performance Assessment of Using Docker for Selected MPI Applications in a Parallel Environment Based on Commodity Hardware
PublicationIn the paper, we perform detailed performance analysis of three parallel MPI applications run in a parallel environment based on commodity hardware, using Docker and bare-metal configurations. The testbed applications are representative of the most typical parallel processing paradigms: master–slave, geometric Single Program Multiple Data (SPMD) as well as divide-and-conquer and feature characteristic computational and communication...
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Benchmarking Parallel Chess Search in Stockfish on Intel Xeon and Intel Xeon Phi Processors
PublicationThe paper presents results from benchmarking the parallel multithreaded Stockfish chess engine on selected multi- and many-core processors. It is shown how the strength of play for an n-thread version compares to 1-thread version on both Intel Xeon and latest Intel Xeon Phi x200 processors. Results such as the number of wins, losses and draws are presented and how these change for growing numbers of threads. Impact of using particular...
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Benchmarking Performance of a Hybrid Intel Xeon/Xeon Phi System for Parallel Computation of Similarity Measures Between Large Vectors
PublicationThe paper deals with parallelization of computing similarity measures between large vectors. Such computations are important components within many applications and consequently are of high importance. Rather than focusing on optimization of the algorithm itself, assuming specific measures, the paper assumes a general scheme for finding similarity measures for all pairs of vectors and investigates optimizations for scalability...
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Performance Evaluation of the Parallel Codebook Algorithm for Background Subtraction in Video Stream
PublicationA background subtraction algorithm based on the codebook approach was implemented on a multi-core processor in a parallel form, using the OpenMP system. The aim of the experiments was to evaluate performance of the multithreaded algorithm in processing video streams recorded from monitoring cameras, depending on a number of computer cores used, method of task scheduling, image resolution and degree of image content variability....
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Seasonal and spatial differences in metal and metalloid concentrations in the snow cover of Hansbreen, Svalbard
PublicationMetals and metalloids in snow on glaciers, depending on the season of deposition, may come from various sources: local rock dust (erosion of the geological substratum), marine aerosol, local human activity (e.g. fuel combustion, waste incineration) and long-range atmospheric transport. Hansbreen glacier, located close to the Polish Polar Station in Svalbard, is a perfect site to study metals and metalloids: it has complex geological...
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Energy losses reduction in the medium voltage cable line – case study
PublicationThe paper presents an analysis of energy losses in a power cable system, which is composed of two 30 kV cable lines. This cable system is located at the seaside holiday area, so the load profile during a year is specific. Energy losses related to reactive power transmission, as well as to currents induced in the sheaths of the cables, are subject to analysis. Measurements were made in the system in order to prepare a computer model...
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Experimental Tests Of Sandwich Beams In The Design Process Of GFRP Shell Footbridge Structure
PublicationThe paper includes selected aspects of the study to elaborate architectural, material and construction design of pedestrian footbridge spans made of composite materials. The considered footbridge is a sandwich-type shell structure. The cooperation of PET foam core with outer lining surfaces is crucial for its load bearing capacity. The paper is aimed to experimental investigation of sandwich beams subjected to bending loading....
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FIReWORK: FIR Filters Hardware Structures Auto-Generator
PublicationThe paper presents application called FIReWORK, that allows for automatic creation of the VHDL hardware structures of FIR filters. Automat- ically generated specialized hardware solutions dedicated to the FPGA and ASIC are commonly known as Intellectual Property Cores. The essential fu- ture of the application is easy initialization of FIR filter parameters in GUI, and then automatically design, calculate and generate the IP Core...
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High-Speed Serial Embedded Deterministic Test for System-on-Chip Designs
PublicationThe paper presents a high-speed serial interface between external tester and Embedded Deterministic Test (EDT) compression logic hosted by SoC designs. With only a single bidirectional link, the system is capable of feeding distributed heterogeneous cores with hundreds of test channels. Moreover, it synergistically supports EDT bandwidth management to improve the overall test performance. A detailed study indicates a high potential...
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Local and global response of sandwich beams made of GFRP facings and PET foam core in three point bending test
PublicationIn the paper behaviour of laminated sandwich beams (FRP face sheet – PET foam core – FRP face sheet) subjected to three point bending is studied. The paper aim is to find practical descriptions enabling effective and accurate estimation of the elastic response, damage and failure of the beams, basing on experiments and static calculations. Therefore a number of tests are described, that were done on laminated coupons and foam specimens...
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Modified Preisach model of hysteresis in multi air gap ferrite core medium frequency transformer
PublicationThis article presents the modified Preisach model of hysteresis for a 3-phase medium frequency transformer in a 100 kW dual active bridge converter. The transformer magnetic core is assembled out of ferrite I-cores, which results in multiple parasitic air gaps. For this transformer, the hysteresis loops were measured and parameters of the Preisach model were determined. The Preisach distribution function is approximated with a...
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Efficiency Evaluation of High Performance Computing Systems Using Data Envelopment Analysis
PublicationThe paper presents an evaluation method of high performance computing (HPC) systems using multicriteria efficiency analysis. The Data Envelopment Analysis approach was applied and adapted to the specifics of HPC, which enabled us to compare relative efficiency of systems considering simultaneously multiple parameters. The analysis is based on the TOP500 list of world largest supercomputers and their parameters such as: the number...
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Recent progress in the development of steroid sulfatase inhibitors – examples of the novel and most promising compounds from the last decade
PublicationThe purpose of this review article is to provide an overview of recent achievements in the synthesis of novel steroid sulfatase (STS) inhibitors. STS is a crucial enzyme in the biosynthesis of active hormones (including estrogens and androgens) and, therefore, represents an extremely attractive molecular target for the development of hormone-dependent cancer therapies. The inhibition of STS may effectively reduce the availability...
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The role of analytical chemistry in the study of the Anthropocene
PublicationThe term “Anthropocene” refers to not yet formalized epoch of geologic time during which geologic processes have been dominated by the human impact. This impact takes on many forms. Biological, physical and chemical changes to the Earth System caused by anthropogenic activity are recorded in natural archives either as new fossil assemblages (neobiota), anthropogenic deposits or a wide variety of pollutants emitted to the environment....
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Multi Queue Approach for Network Services Implemented for Multi Core CPUs
PublicationMultiple core processors have already became the dominant design for general purpose CPUs. Incarnations of this technology are present in solutions dedicated to such areas like computer graphics, signal processing and also computer networking. Since the key functionality of network core components is fast package servicing, multicore technology, due to multi tasking ability, seems useful to support packet processing. Dedicated...
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A 95-Year-Old Concrete Arch Bridge: From Materials Characterization to Structural Analysis
PublicationThe structural analysis of a 95-year-old concrete arch bridge located in Jagodnik (Poland) is performed in this paper, in order to check its behavior under today’s traffic loads. The mechanical properties of both the concrete and the reinforcement are investigated by testing cores and bar stubs extracted from the bridge. Structural analysis confirms that the bridge meets today’s load requirements in terms of bearing capacity, serviceability...
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Analysis of Induced Voltages and Power Losses in High Voltage Power Cables for Selected Methods of Cables Sheaths Bonding
PublicationPower is increasingly supplied to city centres with 110 kV cable lines. This is a convenient way to supply power, and practically the only one possible in areas of dense urban development. A high-voltage cable contains a coaxial metallic sheath, in which in normal operation and in fault conditions (during short-circuits) significant line-to-earth voltages can be induced, which threatens electric shock and/or damage to the cable’s...
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An Automatic Self-Tuning Control System Design for an Inverted Pendulum
PublicationA control problem of an inverted pendulum in the presence of parametric uncertainty has been investigated in this paper. In particular, synthesis and implementation of an automatic self-tuning regulator for a real inverted pendulum have been given. The main cores of the control system are a swing-up control method and a stabilisation regulator. The first one is based on the energy of an inverted pendulum, whereas the second one...
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Parallel implementation of background subtraction algorithms for real-time video processing on a supercomputer platform
PublicationResults of evaluation of the background subtraction algorithms implemented on a supercomputer platform in a parallel manner are presented in the paper. The aim of the work is to chose an algorithm, a number of threads and a task scheduling method, that together provide satisfactory accuracy and efficiency of a real-time processing of high resolution camera images, maintaining the cost of resources usage at a reasonable level. Two...
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Single and Dual-GPU Generalized Sparse Eigenvalue Solvers for Finding a Few Low-Order Resonances of a Microwave Cavity Using the Finite-Element Method
PublicationThis paper presents two fast generalized eigenvalue solvers for sparse symmetric matrices that arise when electromagnetic cavity resonances are investigated using the higher-order finite element method (FEM). To find a few loworder resonances, the locally optimal block preconditioned conjugate gradient (LOBPCG) algorithm with null-space deflation is applied. The computations are expedited by using one or two graphical processing...
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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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Block Conjugate Gradient Method with Multilevel Preconditioning and GPU Acceleration for FEM Problems in Electromagnetics
PublicationIn this paper a GPU-accelerated block conjugate gradient solver with multilevel preconditioning is presented for solving large system of sparse equations with multiple right hand-sides (RHSs) which arise in the finite-element analysis of electromagnetic problems. We demonstrate that blocking reduces the time to solution significantly and allows for better utilization of the computing power of GPUs, especially when the system matrix...
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Effective Permeability of Multi Air Gap Ferrite Core 3-Phase Medium Frequency Transformer in Isolated DC-DC Converters
PublicationThe magnetizing inductance of the medium frequency transformer (MFT) impacts the performance of the isolated dc-dc power converters. The ferrite material is considered for high power transformers but it requires an assembly of type “I” cores resulting in a multi air gap structure of the magnetic core. The authors claim that the multiple air gaps are randomly distributed and that the average air gap length is unpredictable at the...
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Optimization of parallel implementation of UNRES package for coarse‐grained simulations to treat large proteins
PublicationWe report major algorithmic improvements of the UNRES package for physics-based coarse-grained simulations of proteins. These include (i) introduction of interaction lists to optimize computations, (ii) transforming the inertia matrix to a pentadiagonal form to reduce computing and memory requirements, (iii) removing explicit angles and dihedral angles from energy expressions and recoding the most time-consuming energy/force terms...
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Analysis of AC/DC/DC Converter Modules for Direct Current Fast-Charging Applications
PublicationThe paper is a comprehensive laboratory comparison study of two galvanic isolated solution off-board battery chargers: (1) Si-based cost-effective case, and (2) SiC-bidirectional ready for vehicle to grid concept case. All circuits are modular, and in both cases the DC/DC converter can be replaced according to the end user requirements (the coupled transformer remains the same and is constructed based on 12xC100 cores to avoid...
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KernelHive: a new workflow-based framework for multilevel high performance computing using clusters and workstations with CPUs and GPUs
PublicationThe paper presents a new open-source framework called KernelHive for multilevel parallelization of computations among various clusters, cluster nodes, and finally, among both CPUs and GPUs for a particular application. An application is modeled as an acyclic directed graph with a possibility to run nodes in parallel and automatic expansion of nodes (called node unrolling) depending on the number of computation units available....
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Novel tetrahedral cobalt(II) silanethiolates: structures and magnetism
PublicationThree heteroleptic complexes of Co(II) tri-tert-butoxysilanethiolates have been synthesized with piperidine [Co{SSi(OtBu)3}2(ppd)2] 1, piperazine [Co{SSi(OtBu)3}2(NH3)]2(μ-ppz)·2CH3CN 2, and N-ethylimidazole [Co{SSi(OtBu)3}2(etim)2] 3. The complexes have been characterized by a single-crystal X-ray, revealing their tetrahedral geometry on Co(II) coordinated by two nitrogen and two sulfur atoms. Complexes 1 and 3 are mononuclear,...
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Copper(I) halide cluster-based coordination polymers modulated by chiral ditopic dithiodianthranilide ligands: synthesis, crystal structure and photoluminescence
PublicationReaction of copper(I) halides with chiral dithiodianthranilidesmdtaandbdtaafforded polymeric complexeswhere polynuclear CuX clusters were linked together by ditopic bridging ligands into 1D chains or 2D layerstructures. In the case of racemic ligands double stranded chain polymers were formed where the Cu4X4(X = I or Br) cores are connected by enantiomeric pairs of the ditopic ligands. In contrast, a homochiralmdtaligand created...
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Sources and composition of chemical pollution in Maritime Antarctica (King George Island), part 2: Organic and inorganic chemicals in snow cover at the Warszawa Icefield
PublicationThe study area is located on King George Island, where 90% of the area is permanently glaciated. This study provides a comprehensive analysis of the inorganic and organic chemistry of snow cover in the icefield and a comparison against previous results obtained in fresh water. Snow samples were collected in the summer of 2017 in the Warszawa Icefield area. Sampling points are located along two transects: between the Arctowski Polish...
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Selected design and construction aspects of supercritical steam generators for high temperature reactors = Wybrane aspekty konstrukcyjne i projektowe generatorów pary nadkrytycznej ogrzewanych z reaktorów wysokotemperaturowych
PublicationW artykule zaprezentowano uwarunkowania projektowe i konstrukcyjne nadkrytycznego generatora pary (jednoprzepływowego) wykorzystującego do ogrzewania hel z reaktorów HTR i VHTR. Wymiennik helikoidalny jest preferowany dla zwiększenia wymiany ciepła i zwartości. Badano własności czynników wymieniających ciepło z parą w obszarach przy- i nadkrytycznych. Analizowano korelacje, aby wybrać najbardziej wiarygodne. Przedyskutowano najbardziej...
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Crystallographic study of self-organization in the solid state including quasi-aromatic pseudo-ring stacking interactions in 1-benzoyl-3-(3,4-dimethoxyphenyl)thiourea and 1-benzoyl-3-(2-hydroxypropyl)thiourea
Publication1-Benzoylthioureas contain both carbonyl and thiocarbonyl functional groups and are of interest for their biological activity, metal coordination ability and involvement in hydrogen-bond formation. Two novel 1-benzoylthiourea derivatives, namely 1-benzoyl-3-(3,4-dimethoxyphenyl)thiourea, C₁₆H₁₆N₂O₃S, (I), and 1-benzoyl-3-(2-hydroxypropyl)thiourea, C₁₁H₁₄N₂O₂S, (II), have been synthesized and characterized. Compound (I) crystallizes...
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A GPU Solver for Sparse Generalized Eigenvalue Problems with Symmetric Complex-Valued Matrices Obtained Using Higher-Order FEM
PublicationThe paper discusses a fast implementation of the stabilized locally optimal block preconditioned conjugate gradient (sLOBPCG) method, using a hierarchical multilevel preconditioner to solve nonHermitian sparse generalized eigenvalue problems with large symmetric complex-valued matrices obtained using the higher-order finite-element method (FEM), applied to the analysis of a microwave resonator. The resonant frequencies of the low-order...
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DL_MG: A Parallel Multigrid Poisson and Poisson–Boltzmann Solver for Electronic Structure Calculations in Vacuum and Solution
PublicationThe solution of the Poisson equation is a crucial step in electronic structure calculations, yielding the electrostatic potential -- a key component of the quantum mechanical Hamiltonian. In recent decades, theoretical advances and increases in computer performance have made it possible to simulate the electronic structure of extended systems in complex environments. This requires the solution of more complicated variants of the...
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Coastal cliff erosion as a source of toxic, essential and nonessential metals in the marine environment
PublicationDue to the rising environmental awareness, emissions and releases of pollutants, including metals, have been considerably reduced in the last decades. Therefore, the remobiliza-tion of natural and anthropogenic contaminants is gaining importance in their biogeochemical cycle. In the marine coastal zone, this process occurs during the erosion of a shore, especially the most vulnerable cliffs. The research was conducted in the...
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Development and experimental validation of a novel double-stage yield steel slit damper-buckling restrained brace
PublicationThis research is focused on the development and experimental validation of a novel double-stage yield steel slit damper-buckling restrained brace (SSD-DYB) system designed for seismic resistance of steel structures. The SSD-DYB integrates the energy dissipation capability of a steel slit damper (SSD) in its initial segment, enhancing performance in the case of lower seismic intensities levels while employing a larger segment for...
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The application of non-destructive methods in the diagnostics of the approach pavement at the bridges
PublicationThe article presents the possibility of using non-destructive methods of road pavement diagnostics as an alternative to traditional means to assess the reasons for premature cracks adjacent to bridge objects. Two scanning methods were used: laser scanning to measure geometric surface deformation and ground penetrating radar (GPR) inspection to assess the road pavement condition. With the use of a laser scanner, an effective tool...
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Potencjał kognitywno-kulturowy dzielnicy a innowacyjne strategie rehabilitacji w kontekście społecznej indywidualizacji. Studium przypadku: Mouraria, Lizbona = Innovative Public Space Rehabilitation Models to Create Cognitive-Cultural Urban Economy in the Age of Mass Individualisation. Case of Mouraria, Lisbon
PublicationInnovative Public Space Rehabilitation Models to Create Cognitive- -Cultural Urban Economy in the Age of Mass Individualisation. Case of Mouraria, Lisbon. This paper deals with the issue of sustainable urban rehabilitation interventions in city cores focused on value creation through culture-led development as a tool for building a cognitive city. The objective is to analyze cases of rehabilitation of public space by culture-led...
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Solvothermal synthesis and structural characterization of three polyoxotitanium-organic acid clusters
PublicationThree new titanium oxo-clusters Ti4O2(OiPr)10(OOCPhMe)2 (I), Ti6O4(OEt)8(OOCPhMe)8 (II) and Ti6O6(OEt)6(OOCCHPh2)6 (III) were obtained by easy one-step solvothermal reactions of titanium(IV) isopropoxide, alcohols and carboxylic acids. The three compounds were characterized by single-crystal and powder X-ray diffraction, TGA/DSC, optical and electron microscopy, and FTIR and NMR spectroscopy. X-ray powder diffraction and spectroscopy...
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Preconditioners with Low Memory Requirements for Higher-Order Finite-Element Method Applied to Solving Maxwell’s Equations on Multicore CPUs and GPUs
PublicationThis paper discusses two fast implementations of the conjugate gradient iterative method using a hierarchical multilevel preconditioner to solve the complex-valued, sparse systems obtained using the higher order finite-element method applied to the solution of the time-harmonic Maxwell equations. In the first implementation, denoted PCG-V, a classical V-cycle is applied and the system of equations on the lowest level is solved...
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Spatial and vertical distribution analysis of heavy metals in urban retention tanks sediments: a case study of Strzyza Stream
PublicationConcentrations of seven heavy metals (HMs): Zn, Cu, Pb, Cd, Ni, Cr, and Fe in core samples of bottom sediments from four retention tanks (RTs) located along the Strzyza Stream in northern Poland (Gdansk) were measured to obtain a general view of sediment quality. The recognition of contamination and potential environmental impacts is the main aim of this paper. A total of 96 sediment samples were collected from eight sampling sites...