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Potato Juice, a Starch Industry Waste, as a Cost-Effective Medium for the Biosynthesis of Bacterial Cellulose
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Characteristics of the (Mn-N-O-P) type layers created on the cast aluminium alloys
PublicationPrzedstawiono skład chemiczny i fazowy, a także właściwości korozyjne i tribologiczne warstw powierzchniowych typu (Mn-N-O-P) wytworzonych na odlewniczych stopach aluminium. Warstwy typu (Mn-N-O-P) wielokrotnie podnoszą zarówno właściwości tribologiczne jak i korozyjne odlewniczych stopów aluminium z krzemem.
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Insight into the microstructural and durability characteristics of 3D printed concrete: Cast versus printed specimens
PublicationThis study presents the comparison of microstructural and durability characteristics of 3D printed concrete (3DPC) depending on its production method (printing or casting). Printed samples with different numbers of layers, as well as a cast specimen with an identical mix composition, were produced and compared, with their microstructural pore and solid characteristics quantitatively and qualitatively investigated. For this purpose,...
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The cost of reproduction in women: Reproductive effort and oxidative stress in premenopausal and postmenopausal American women
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Cost Effectiveness of Open Repair of Abdominal Aortic Aneurysms with a Novel Peri-Operative Bundle
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A tribological research on a reciprocating sliding contact of aluminum-ferrous composite against cast-iron.
PublicationOpisano badania kompozytów: silumin AlSi11-żelazo albo silumin AlSi11-stal narzędziowa N9 (otrzymanych in situ), a także samego siluminu AlSi11 w skojarzeniu z żeliwem 350, przy tarciu ślizgowym w ruchu posuwisto-zwrotnym. Stwierdzono wpływ sposobu otrzymywania materiału kompozytowego na zużycie i opory ruchu skojarzenia badawczego, w szczególności materiały te zużywały się wolniej, niż silumin AlSi11.
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A new method for searching optimal path on a raster plane including cost of direction changes
PublicationArtykuł przedstawia nowy algorytm znajdowania optymalnych tras na siatkach rastrowych. Szczegółowo opisano zastosowane struktury danych, dzięki który algorytm ma liniową złoŻoność obliczeniową. Zamieszczono również propozycje możliwych zastosowań.
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Reduced-cost surrogate modelling of compact microwave components by two-level kriging interpolation
PublicationFull-wave electromagnetic (EM) analysis is a versatile tool for evaluating the performance of high-frequency components. Its potential drawback is its high computational cost, inhibiting the execution of EM-driven tasks requiring massive simulations. The applicability of equivalent network models is limited owing to the topological complexity of compact microstrip components because of EM cross-coupling effects. Development of...
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Evaluation of RTKLIB's Positioning Accuracy Using low-cost GNSS Receiver and ASG-EUPOS
PublicationThe paper focuses on a comparison of different positioning methods provided by free and open source software (FOSS) package called RTKLIB. The RTKLIB supports real‐time and post‐processed positioning. The most important modes of operation tested by the authors are Kinematic, Static, Fixed and Precise Point Positioning (PPP). The data for evaluation were obtained from low‐cost Global Navigation Satellite System (GNSS) receiver....
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Cost-Effective and Sufficiently Precise Integration Method Adapted to the FEM Calculations of Bone Tissue
PublicationThe technique of Young’s modulus variation in the finite element is not spread in biomechanics. Our future goal is to adapt this technique to bone tissue strength calculations. The aim of this paper is to present the necessary studies of the element’s integration method that takes into account changes in material properties. For research purposes, a virtual sample with the size and distribution of mechanical properties similar...
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Accuracy of a low-cost autonomous hexacopter platforms navigation module for a photogrammetric and environmental measurements
PublicationA photogrammetry and environmental measurements from an unmanned aerial vehicle (UAV) are a low-cost alternative for a traditional aerial photogrammetry. A commercial off-the-shelf products (COTS) offers a variety of cheap components that a suitable to be used on board a UAV. In this paper a low-cost navigation module based on Ublox NEO-M8N GPS and Pixhawk flight controller have been described, as a main extrinsic parameters source...
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Reduced-Cost Design Optimization of High-Frequency Structures Using Adaptive Jacobian Updates
PublicationElectromagnetic (EM) analysis is the primary tool utilized in the design of high-frequency structures. In vast majority of cases, simpler models (e.g., equivalent networks or analytical ones) are either not available or lack accuracy: they can only be used to yield initial designs that need to be further tuned. Consequently, EM-driven adjustment of geometry and/or material parameters of microwave and antenna components is a necessary...
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Analysis of exhaled breath for dengue disease detection by low-cost electronic nose system
PublicationThis paper presents a procedure and a set-up of an electronic nose system analyzing exhaled breath to detect the patients suffering from dengue – a mosquito-borne tropical disease. Low-power resistive gas sensors (MiCS-6814, TGS8100) were used to detect volatile organic compounds (VOCs) in the exhaled breath. The end-tidal phase of patients exhaled breath was collected with a BioVOCTM breath sampler. Two strategies were assessed...
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Neural network based algorithm for hand gesture detection in a low-cost microprocessor applications
PublicationIn this paper the simple architecture of neural network for hand gesture classification was presented. The network classifies the previously calculated parameters of EMG signals. The main goal of this project was to develop simple solution that is not computationally complex and can be implemented on microprocessors in low-cost 3D printed prosthetic arms. As the part of conducted research the data set EMG signals corresponding...
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Conservation aspects of cast-iron platform shelters on the example of Vistula Pomerania railway stations
PublicationCast-iron shelters were used in the 19th century as cheaper alternatives to large platform halls. Nevertheless, they were aesthetically distinguishable from later riveted solutions. Because of their durability and continuous utility, they were not the subject of disassembly, as numerous transport infrastructure objects have been in recent decades. This article aims to indicate proper conservation practices during construction works...
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The In-House Method of Manufacturing a Low-Cost Heat Pipe with Specified Thermophysical Properties and Geometry
PublicationVarious types of heat pipes are available to purchase off the shelf, from various manufacturers, but most of them have strictly defined geometry and technical parameters. However, when there is a need to use a heat pipe (HP) with an unusual size and shape or working conditions other than the standard ones, it becomes very costly to order them from manufacturers, especially in small quantities, and only a few producers are willing...
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A Low-Cost System for Far-Field Non-Anechoic Measurements of Antenna Performance Figures
PublicationPrototype measurements are the key step in the development of antenna structures. Typically, their far-field characteristics are validated in expensive, dedicated facilities such as open range sites, or anechoic chambers. Despite being necessary for obtaining high-precision data (e.g., for device qualification), the use of costly infrastructure might not be fully justified when the main goal of measurements includes demonstration...
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New methodology for calculating cost-efficiency of different ways of voting: is internet voting cheaper?
PublicationNew ways of voting in elections are being sought by electoral administrations worldwide who want to reverse declining voter turnouts without increasing electoral budgets. This paper presents a novel approach to cost accounting for multi-channel elections based on local elections in Estonia. By doing so, it addresses an important gap in the academic literature in this field. The authors confirm that internet voting was most cost-efficient...
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Polygons vs. clumps of discs: A numerical study of the influence of grain shape on the mechanical behaviour of granular materials
PublicationWe performed a series of numerical vertical compression tests on assemblies 01 20 granular material using a Discrete Element code and studied the results with regard to the grain shape. The samples consist of 5000 grains made from either 3 overlapping discs (clumps - grains with concavities) or six-edged polygons (convex grains). These two grain type have similar external envelope, which is a fund ion of a geometrical parameter...
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Apparent molar volumes and compressibilities of lanthanum, gadolinium, lutetium and sodium trifluoromethanesulfonates in N,N-dimethylformamide and N,N-dimethylacetamide
PublicationZmierzono gęstości roztworów trifluorometanosulfonianów lantanu, gadolinu i lutetu w N,N-dimetyloformamidzie i N,N-dimetyloacetamidzie w szerokim zakresie temperatur. W oparciu o uzyskane wartości gęstości wyznaczono pozorne objętości molowe, cząstkowe objętości molowe oraz rozszerzalności izobaryczne. Dodatkowo zmierzono szybkości rozchodzenia się dźwięku w badanych roztworach w 298,15 K i wyznaczono pozorne ściśliwości molowe...
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The Impact of Common Epidemiological Factors on Gray and White Matter Volumes in Magnetic Resonance Imaging–Is Prevention of Brain Degeneration Possible?
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Postępowanie w przypadku wymiany eluentu/kolumny. Niektóre przyczyny nieprawidłowej pracy chromatografu i sposoby ich usuwania.
PublicationPROSZĘ O 2 ZDANIA STRESZCZENIA
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Apparent Molar Volumes and Isentropic Compressibilities of Tetraalkylammonium Bromides in Aqueous Propane-1,2-diol. An Attempt to Design Hydraulic Liquids
PublicationApparent molar volumes and apparent molar compressibilities for tetramethylammonium, tetraethylammonium, tetrapropylammonium, and tetrabutylammonium bromides in water, propane-1,2-diol, and water−propane-1,2-diol mixtures (mass fraction: 0.25, 0.50, and 0.75) have been determined from solution density measurements at T = 288.15, 293.15, 298.15, 303.15, 308.15, 313.15, and 318.15 K and sound velocity measurements at T = 298.15 K...
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Modyfikacja połączenia dźwigara ze słupem w konstrukcji stalowej Terminalu T2 Portu Lotniczego w Gdańsku
PublicationW2015 r. ukończono rozbudowę Terminalu T2 Portu Lotniczego im. Lecha Wałęsy wGdańsku. Politechnika Gdańska pełniła nadzór naukowy nad rozbudową obiektu. Wykonano wiele analiz, których celem była weryfikacja pracy konstrukcji w fazach montażu oraz w stanie docelowym. Wnioski z przeprowadzonych badań doprowadziły do modyfikacji oparcia dźwigarów dachowych na stalowych słupach nośnych, z uwagi na stwierdzone lokalne przekroczenia...
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Wielokapilarna chromatografia gazowa
PublicationPrzedstawiono budowę i charakterystykę analityczną nowego typu kolumn dochromatografii gazowej. Omówiono cechy odróżniając wielokapilarne kolumny dochromatogragii gazowej od innych typów kolumn chromatograficznych. Wskazanona możliwości ich zastosowania oraz korzyści wynikające z ich wykorzystania.
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Low-Cost Multi-Objective Optimization of Antennas By Means Of Generalized Pareto Ranking Bisection Algorithm
PublicationThis paper introduces a generalized Pareto ranking bisection algorithm for low-cost multi-objective design optimization of antenna structures. The algorithm allows for identifying a set of Pareto optimal sets of parameters (that represent the best trade-offs between considered objectives) by iterative partitioning of the intervals connecting previously found designs and executing a Pareto-ranking-based poll search. The initial...
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Low-cost multi-objective optimization of antennas using Pareto front exploration and response features
PublicationIn the paper, a procedure for low-cost multi-objective optimization of antenna structures is presented. Our approach is based on exploration of the Pareto front representing the best possible trade-offs between conflicting objectives, here, the structure size and its electrical performance. Starting from the design representing the best in-band reflection level, subsequent Pareto-optimal designs are identified through local constrained...
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Identifying Surface Runoff Pathways for Cost-Effective Mitigation of Pollutant Inputs to Drinking Water Reservoir
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The Risk Indicators of Construction Projects’ Cost Overruns Assessed with PCA, Decision Trees, and Pearson’s Correlations
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Comparison between industrial and simulated textile wastewater treatment by AOPs – Biodegradability, toxicity and cost assessment
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New Low-Cost Video Camera Pointing Mechanism for Stratospheric Balloons: Design and Operational Tests
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On the Microstructure, Microhardnessand Wear Behavior of Gray Cast Iron Surface Layer after Laser Strengthening
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Cast aluminium matrix composites modified with using FSP process – Changing of the structure and mechanical properties
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Multiobjective Water Distribution Systems Control of Pumping Cost, Water Quality, and Storage-Reliability Constraints
PublicationThis work describes a multiobjective model for trading-off pumping cost and water quality for water distribution systems operation. Constraints are imposed on flows and pressures, on periodical tanks operation, and on tanks storage. The methodology links the multiobjective SPEA2 algorithm with EPANET, and is applied on two example applications of increasing complexity, under extended period simulation conditions and variable energy...
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Low-Cost Multi-Objective Optimization Yagi-Uda Antenna in Multi-Dimensional Parameter Space
PublicationA surrogate-based technique for fast multi-objective optimization of a multi-parameter planar Yagi-Uda antenna structure is presented. The proposed method utilizes response surface approximation (RSA) models constructed using training samples obtained from evaluation of the low-fidelity antenna model. Utilization of the RSA models allowsfor fast determination of the best possible trade-offs between conflicting objectives in multi-objective...
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Low-cost EM-Simulation-based Multi-objective Design Optimization of Miniaturized Microwave Structures
PublicationIn this work, a simple yet reliable technique for fast multi-objective design optimization of miniaturized microwave structures is discussed. The proposed methodology is based on point-by-point identification of a Pareto-optimal set of designs representing the best possible trade-offs between conflicting objectives such as electrical performance parameters as well as the size of the structure of interest. For the sake of computational...
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Low Cost Hexacopter Autonomous Platform for Testing and Developing Photogrammetry Technologies and Intelligent Navigation Systems
PublicationLow-cost solutions for autonomous aerial platforms are being intensively developed and used within geodetic community. Unmanned aerial vehicles are becoming very popular and widely used for photogrammetry and remote sensing applications. Today’s market offers an affordable price components for unmanned solution with significant quality and accuracy growth. Every year market offers a new solutions for autonomous platforms with better...
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On deterministic procedures for low-cost multi-objective design optimization of miniaturized impedance matching transformers
PublicationPurpose This paper aims to investigate deterministic strategies for low-cost multi-objective design optimization of compact microwave structures, specifically, impedance matching transformers. The considered methods involve surrogate modeling techniques and variable-fidelity electromagnetic (EM) simulations. In contrary to majority of conventional approaches, they do not rely on population-based metaheuristics, which permit lowering...
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Cost-Efficient EM-Driven Size Reduction of Antenna Structures by Multi-Fidelity Simulation Models
PublicationDesign of antenna systems for emerging application areas such as the Internet of Things (IoT), fifth generation wireless communications (5G), or remote sensing, is a challenging endeavor. In addition to meeting stringent performance specifications concerning electrical and field properties, the structure has to maintain small physical dimensions. The latter normally requires searching for trade-off solutions because miniaturization...
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Reduced-Cost Two-Level Surrogate Antenna Modeling using Domain Confinement and Response Features
PublicationElectromagnetic (EM) simulation tools have become indispensable in the design of contemporary antennas. Still, the major setback of EM-driven design is the associated computational overhead. This is because a single full-wave simulation may take from dozens of seconds up to several hours, thus, the cost of solving design tasks that involve multiple EM analyses may turn unmanageable. This is where faster system representations (surrogates)...
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Low-Cost Unattended Design of Miniaturized 4 × 4 Butler Matrices with Nonstandard Phase Differences
PublicationDesign of Butler matrices dedicated to Internet of Things and 5th generation (5G) mobile systems—where small size and high performance are of primary concern—is a challenging task that often exceeds capabilities of conventional techniques. Lack of appropriate, unified design approaches is a serious bottleneck for the development of Butler structures for contemporary applications. In this work, a low-cost bottom-up procedure for...
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Low-cost 3D Printed Circularly Polarized Lens Antenna for 5.9 GHz V2X Applications
PublicationThis paper presents design and realization of a circularly polarized antenna consisting of a linearly polarized patch antenna and a 3D printed lens, at the same time performing the functions of wave collimator and a polarizer. The antenna is dedicated for 802.11p systems, as a part of road infrastructure, with operation bandwidth 5.85 - 5.925 GHz. Its realised gain and axial ratio at center frequency 5.9 GHz are 14.3 dBi and 2.17...
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A Surrogate-Assisted Measurement Correction Method for Accurate and Low-Cost Monitoring of Particulate Matter Pollutants
PublicationAir pollution involves multiple health and economic challenges. Its accurate and low-cost monitoring is important for developing services dedicated to reduce the exposure of living beings to the pollution. Particulate matter (PM) measurement sensors belong to the key components that support operation of these systems. In this work, a modular, mobile Internet of Things sensor for PM measurements has been proposed. Due to a limited...
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Cost-Efficient Bi-Layer Modeling of Antenna Input Characteristics Using Gradient Kriging Surrogates
PublicationOver the recent years, surrogate modeling has been playing an increasing role in the design of antenna structures. The main incentive is to mitigate the issues related to high cost of electromagnetic (EM)-based procedures. Among the various techniques, approximation surrogates are the most popular ones due to their flexibility and easy access. Notwithstanding, data-driven modeling of antenna characteristics is associated with serious...
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High-performance liquid chromatography thermodynamic study of new potential antiepileptic compounds on a cholesterol column using isocratic elution with methanol/water and acetonitrile/water eluent systems
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Excess volumes of mixing in (N,N-Dimethylacetamide+methanol+water) and (N,N-Dimethylacetamide+ethanol+water) at the temperature 313.15 K
PublicationW pracy podane są rezultaty precyzyjnych pomiarów namiarowych objętości molowych dla dwóch układów trójskładnikowych zawierających wodę, amid alifatyczny (N,N-dimetyloacetamid) oraz alkohol: metanol lub etanol. Dla wszystkich badanych układów obserwowane są duże i ujemne wartości nadmiarowych objętości mieszania, wskazujące na obecność silnych oddziaływań międzycząsteczkowych.
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Radiation Therapy-Related Changes in Serum Proteome Patterns Are Affected by Medium Doses of Radiation Delivered to Large Volumes of Normal Tissue
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Limiting Partial Molar Volumes of Tetra-n-Alkylammonium Perchlorates in N,N-dimethylacetamide, Triethylphosphate and Dimethyl Sulfoxide at 298.15 K
PublicationThe densities of tetraalkylammonium perchlorates R4NClO4(R = methyl, or ethyl, or propyl, or butyl) and ammonium perchlorate solutions in N, N - dimethylacetamide, dimethyl sulfoxide, and triethylphosphate have been measured over the whole composition range atT = 298.15 K. From these densities, apparent and limiting partial molar volumes of the electrolytes and ions...
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Coordination states and apparent molar volumes of cobalt(II) perchlorate and cobalt(II) chloride in N,N-diethylacetamide at 25 C
PublicationWyznaczono pozorne objętości molowe Co(ClO4)2 i CoCl2 oraz elektronowe widma absorpcyjne w zakresie widzialnym roztworów Co(ClO4)2, CoCl2, Co(ClO4)2 - CoCl2, CoCl2 - LiCl w N,N-dietyloacetamidzie. Analiza pozornych objętości molowych, oraz wpływu temperatury i składu roztworów umozliwiła zidentyfikowanie kompleksów chlorkowych kobaltu(II) powstających w układzie Co(2+)-Cl(-)-DEA. Wyznaczono stałe trwałości.
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Thermodynamic properties of inorganic salts in nonaqueous solvents. II. Apparent molar volumes and compressibilities of divalent transition-metal perchlorates in acetonitrile
PublicationW oparciu w wyniki pomiarów gęstości wykonanych w temperaturze 15,20,25,30,35,40 i 50 stopni Celsjusza oraz pomiaru szybkości dżwięku w temperaturze 25 stopni Celsjusza, wyznaczono pozorne objętości molowe oraz ściśliwości adiabatyczne roztworów nadchloranów manganu(II), kobaltu(II), niklu(II) i cynku(II). Obliczono odpowiednie wartości standardowe oraz rozszerzalności izobaryczne. Przeanalizowano związki między strukurą elektronową...