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Buckling and initial post-local buckling behaviour of cold-formed channel member flange
PublicationThe initial post-buckling behaviour of a cold-formed channel member flange after its local buckling is investigated. An axially compressed column or beam subjected to pure bending is considered. The member material is assumed to follow a linear stress-strain relationship. The governing non-linear differential equation of the problem is derived using the minimum total potential energy principle. An approximate solution for the equation...
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Miniaturized methods of sample preparation
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Comparing phylogenetic trees using a minimum weight perfect matching
PublicationA phylogenetic tree represents historical evolutionary relationshipbetween different species or organisms. There are various methods for reconstructing phylogenetic trees.Applying those techniques usually results in different treesfor the same input data. An important problem is to determinehow distant two trees reconstructed in such a wayare from each other. Comparing phylogenetic trees is alsouseful in mining phylogenetic information...
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Power quality conditioners with minimum number of current sensor requirement
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Measures for interoperability of phenotypic data: minimum information requirements and formatting
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Sample preparation procedure for the determination of polycyclic aromatic hydrocarbons in petroleum vacuum residue and bitumen
PublicationThis paper describes a novel method of samplepreparation for the determination of trace concentrations ofpolycyclic aromatic hydrocarbons (PAHs) in high-boilingpetroleum products. Limits of quantitation of the investigatedPAHs in materials of this type range from tens ofnanograms per kilogram to <20 μg/kg. The studies revealedthat in order to separate most of interferences from theanalytes without a significant loss of PAHs, it...
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DETERMINATION OF SP3 FRACTION IN ta-C COATING USING XPS AND RAMAN SPECTROSCOPY
PublicationThe paper presents results of studies on the structure of tetrahedral amorphous carbon films (ta-C) with a thickness in the range from 20 to 280 nm, deposited using pulsed vacuum arc technique with an electromagnetic Venetian blind plasma filter. The results of the phase structure analysis, obtained using visible Raman spectroscopy and UV Raman spectroscopy methods, showed a strong dependence of the results on the presence, on...
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MECHANICAL PROPERTIES OF BOTTOM ASH – DREDGED MATERIAL MIXTURES IN LABORATORY TESTS
PublicationBottom ash from EC Gdańsk and dredged material taken from the mouth of The Vistula were mixed to form an engineering material used for dike construction. Mixtures with different bottom ash content were tested in laboratory to determine its basic physical and mechanical properties. The optimum bottom ash–dredged material mixture, built in the corps of the test dike, contains 70% of ash. The optimum bottom ash content in the mixture...
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The complexity of bicriteria tree-depth
PublicationThe tree-depth problem can be seen as finding an elimination tree of minimum height for a given input graph G. We introduce a bicriteria generalization in which additionally the width of the elimination tree needs to be bounded by some input integer b. We are interested in the case when G is the line graph of a tree, proving that the problem is NP-hard and obtaining a polynomial-time additive 2b-approximation algorithm. This particular...
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Effect of oxygenation time on signal of a sensor based on ionic liquids
PublicationThe paper presents an oxygen sensor based on ionic liquids and solid electrodes. The following ionic liquids have been employed: [BMIM][BF4], [HMIM][Cl], [BMIM][N(CN2)]. Minimum time of the sensor exposure to analyte, after which the signal (current intensity) was stable, has been evaluated. An impact of volumetric flow rate of analyte on the sensor exposure time and signal has been determined. A product of permeability coefficient...
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Evaluation of Pavement Temperatures in Poland During Winter Conditions
PublicationThe paper presents the analysis of pavement temperatures from meteorological stations located at the Polish national roads during the impact of low winter temperatures. Presented issue is particularly important in view of the problem of low-temperature cracks that occur in the asphalt pavement under the influence of low temperatures. For each location of meteorological station there were analysed measurements of the temperature...
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Seismic gap between buildings founded on different soil types experiencing pounding during earthquakes
PublicationSeveral formulas have been suggested in the literature to evaluate the minimum seismic gap that would prevent collisions between adjacent buildings during earthquakes, including those based on the absolute sum of the peak displacements (ABS), square root of the sum of the squares (SRSS), the double difference method (DDC), Australian code, and approach proposed by Naderpour et al. The aim of the present study is to evaluate the...
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Surfactants application in sample preparation techniques: Insights, trends, and perspectives
PublicationSince the implementation of Green Chemistry into analytical practice, significant efforts have been made to improve the sustainability of chemical analysis. These include reducing the use of hazardous chemicals and solvents, minimizing waste, and improving energy efficiency. Surfactants can be applied in chemical analysis as an environmentally friendly alternative to conventional solvents and chemicals. The use of surfactants can...
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Advances in Sample Preparation
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Size effect in concrete under splitting tension
PublicationThe size effect is a fundamental phenomenon in concrete materials. It denotes that both the nominal structural strength and material ductility always decrease with increasing element size under tension. In the paper splitting tensile tests on cylindrical concrete specimens with the different diameter were carried out. Two types of the loading strip (plywood board and steel cylinder) were used. The concrete strength and ductility...
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Quechers sample preparation method variants for analysis of pesticide residues in fruits and vegetables
PublicationThis article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography coupled to MS or ECD for detection. The sample preparation approach is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged and safe. It is a combination of liquid-liquid...
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Identyfikacja parametrów zastępczego schematu elektrycznego krwiobiegu nerki na podstawie niepełnych danych pomiarowych : The parameters identification of the equivalent electric circuit of the kidney blood circulation basis on incomplete measuring date
PublicationW referacie przedstawiono metodę identyfikacji parametrów elektrycznego schematu zastępczego odwzorowującego przepływ krwi przez nerkę. Napięcie potraktowano jako sygnał wejściowy, któremu w hemodynamice odpowiada ciśnienie, natomiast prąd jako sygnał wyjściowy, któremu odpowiada przepływ krwi. Przebieg napięcia aproksymowano funkcją sklejaną w celu uproszczenia procedury pomiarowej i ograniczenia fluktuacji związanych z przebiegiem...
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Zastosowanie filtracji przestrzennej do eliminacji spoofingu w systemie GPS
PublicationArtykuł podejmuje problematykę przeciwdziałania atakowi elektronicznemu typu spoofing w systemie GPS, polegającemu na niepowołanej transmisji imitacji sygnałów odbieranych z satelitów nawigacyjnych tego systemu. Odbiór sygnałów imitujących powoduje wyznaczenie nieprawidłowych wskazań czasu, położenia i prędkości odbiornika GPS. Proponowaną w artykule metodą ochrony odbiornika przed działaniem sygnałów imitujących jest adaptacyjna...
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Can Evaluation Patterns Enable End Users to Evaluate the Quality of an e-learning System? An Exploratory Study.
PublicationThis paper presents the results of an exploratory study whose main aim is to verify if the Pattern-Based (PB) inspection technique enables end users to perform reliable evaluation of e-learning systems in real work-related settings. The study involved 13 Polish and Italian participants, who did not have an HCI background, but used e-learning platforms for didactic and/or administrative purposes. The study revealed that the participants...
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Fast Multi-Objective Optimization of Narrow-Band Antennas Using RSA Models and Design Space Reduction
PublicationComputationally efficient technique for multi-objective design optimization of narrow-band antennas is presented. In our approach, the corrected low-fidelity antenna model (obtained through coarse-discretization EM simulations) is enhanced using frequency scaling and response correction, sampled, and utilized to obtain a fast response surface approximation (RSA) antenna surrogate. The RSA model is constructed in the reduced design space....
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On the partition dimension of trees
PublicationGiven an ordered partition Π={P1,P2,…,Pt} of the vertex set V of a connected graph G=(V,E), the partition representation of a vertex v∈V with respect to the partition Π is the vector r(v|Π)=(d(v,P1),d(v,P2),…,d(v,Pt)), where d(v,Pi) represents the distance between the vertex vv and the set Pi. A partition Π of V is a resolving partition of G if different vertices of G have different partition representations, i.e., for every...
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A method to synthesise groove cam Geneva mechanisms with increased dwell period
PublicationThe present study develops a method to synthesise the groove cam Geneva mechanism with increased dwell period. The main condition of the synthesis is to provide the desired law of motion of the wheel. Additional synthesis conditions are the limitation of the maximum pressure angle and the limitation of the minimum curvature radius of the cam profile. Unlike the conventional Geneva mechanisms, the synthesised groove cam Geneva mechanisms...
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Experimental study on static and dynamic properties of polymer mass
PublicationA new method of repairing damaged structures by filling the cracks with a specially prepared polymer mass has been recently proposed. This new and innovative technique, known as the Flexible Joint Method (FJM), is mainly dedicated to masonries and historical objects, where minimum intervention is permitted. The flexible joint bonds the disrupted elements and ensures further safe exploitation of a damaged structure. The aim of the...
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Modelowanie przestrzennego rozkładu natężenia magnetycznego pola rozproszonego dla wad wzorcowych w płytach
PublicationW pracy przedstawiono model, przy pomocy którego można obliczyć wektor indukcji rozproszonego pola magnetycznego od wady. Przeprowadzono badania eksperymentalne służące weryfikacji tego modelu. W badaniach wykorzystano dwie wady o geometrii prostopadłościanu wydrążone elektro-iskrowo w stalowej płycie. Dla składowej normalnej wektora indukcji pola magnetycznego występowały najmniejsze rozbieżności pomiędzy wynikami pomiarowymi...
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A lower bound on the double outer-independent domination number of a tree
PublicationA vertex of a graph is said to dominate itself and all of its neighbors. A double outer-independent dominating set of a graph G is a set D of vertices of G such that every vertex of G is dominated by at least two vertices of D, and the set V(G)D is independent. The double outer-independent domination number of a graph G, denoted by gamma_d^{oi}(G), is the minimum cardinality of a double outer-independent dominating set of G. We...
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Experimental examination of an elastomeric polymer
PublicationA new method of repairing damaged structures by filling the cracks with a specially prepared elastomeric polymer mass has been recently proposed. This new and innovative technique, known as the Flexible Joint Method (FJM), is mainly dedicated to masonries and historical objects, where minimum intervention is permitted. The flexible joint bonds the disrupted elements and ensures further safe exploitation of a damaged structure....
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Single-Anchor Indoor Localization Using ESPAR Antenna
PublicationIn this paper a new single-anchor indoor localization concept employing Electronically Steerable Parasitic Array Radiator (ESPAR) antenna has been proposed. The new concept uses a simple fingerprinting algorithm adopted to work with directional main beam and narrow minimum radiation patterns of ESPAR antenna that scans 360° area around the base station, while the signal strength received from a mobile terminal is being recorded...
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Pyrolysis of RDF and Catalytic Decomposition of the Produced Tar in a Char Bed Secondary Reactor as an Efficient Source of Syngas
PublicationOne of the technical limitations of refuse-derived fuel (RDF) pyrolysis is the high content of tar in its gas products. In order to resolve this problem, a two-stage RDF pyrolysis with a catalyst based on char from RDF pyrolysis is proposed. This paper presents the results of municipal waste pyrolysis beginning in an oven heated to 480 °C and ending with catalytic tar cracking carried out in the temperature range from 800 to 1000...
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Natural ventilation performance of family building in cold climate during windless time
PublicationIn this paper, the field measurements results are presented on the stack ventilation effect. The paper presents the results of performance (air change rate ACH) natural ventilation for building with inlet gap measured for the transitional season (between heating and summer season). The measurements were performed during a windless time. The house was located in northern Poland, in a cold climate region. The measurement system...
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Produkty strukturyzowane Alior Banku SA i ich efektywność
PublicationProdukty strukturyzowane, realizując potrzeby inwestorów, dają szansę na osiąganie wysokich zysków, przy jednoczesnej możliwości korzystania z ochrony kapitału. Do niedawna produkty strukturyzowane w Polsce były skierowane głównie do inwestorów o zasobniejszych portfelach, w ramach oferty private banking, obecnie są coraz bardziej popularne i dostępne dla wszystkich. Stało się to za sprawą obniżenia minimum inwestycyjnego struktur....
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Similarities and Differences Between the Vertex Cover Number and the Weakly Connected Domination Number of a Graph
PublicationA vertex cover of a graph G = (V, E) is a set X ⊂ V such that each edge of G is incident to at least one vertex of X. The ve cardinality of a vertex cover of G. A dominating set D ⊆ V is a weakly connected dominating set of G if the subgraph G[D]w = (N[D], Ew) weakly induced by D, is connected, where Ew is the set of all edges having at least one vertex in D. The weakly connected domination number γw(G) of G is the minimum cardinality...
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Fake VIP Attacks and Their Mitigation via Double-Blind Reputation
PublicationIn a generic setting subsuming communication networks, resource sharing systems, and multi-agent communities, a client generates objects of various classes carrying class-dependent signatures, to which a server assigns class-dependent service quality. A Fake VIP attack consists in false declaration of a high class, with an awareness that detection of object signature at the server side is costly and so invoked reluctantly. We show...
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Influences of grain shape and size distribution on permeability
PublicationThe present study investigates the effects of shape and size distributions of grains on the coefficient of permeability (k). A series of constant head permeability tests were performed to characterize the coefficient of permeability. Three particle size ranges (4.75- 0.075, 1.18- 0.075 and 0.300-0.075 mm) of two different sands (Narli Sand, Crushed Stone Sand) having different shapes were tested in a constant head permeability...
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HRV and BPV indices in differentiating OSA patients from healthy controls
Open Research DataThe various HRV and BPV indices computed for the purpose of the analyses described in the paper “Differentiating patients with obstructive sleep apnea from healthy controls based on heart rate–blood pressure coupling quantified by entropy-based indices” by P. Pilarczyk, G. Graff, J.M. Amigó, K. Tessmer, K. Narkiewicz, and B. Graff.
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Determination of pesticide residues in fruits and vegetables using QuEChERS sample preparation method
PublicationThe intensive development of agriculture means that more and more toxic organic and inorganic compounds are entering the environment. Because of their widespread use, environmental stability, selective toxicity and bioaccumulative capability, pesticides belong to the most hazardous substances contaminating the environment. They are particularly dangerous in fruits and vegetables, because they are one of the reasons why people are...
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Mechanics of Micro- and Nano-Size Materials and Structures
PublicationNanotechnology knowledge is always looking to expand its boundaries to achieve the mostsignificant benefit to human life and meet the growing needs of today. In this case, we can refer tomicro- and nanosensors in micro/nano-electromechanical systems (MEMS/NEMS). These electricaldevices can detect minimal physical stimuli up to one nanometer in size. Today, micro/nano-sensordevices are widely used in the...
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Metrological analysis of surface quality aspects in minimum quantity cooling lubrication
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Coacervative extraction as a green technique for sample preparation for the analysis of organic compounds
PublicationOne of the present trends in analytical chemistry is miniaturization, which is one of the methods of green analytical chemistry application. A particular emphasis is placed on the elimination of the use of large amounts of organic solvents which are toxic and harmful to the environment, maintaining high efficiency of the extraction process, high recovery values and low values of quantification (LOQ) and detection (LOD) limits....
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Size Exclusion Coupled to Reversed Phase Liquid Chromatography for the Characterization of Cranberry Products
PublicationA combination of solvent extraction, size exclusion purification, and reversed-phase liquid chromatography with UV absorption and fluorescence detection was here used for the determination of flavan-3-ols and related oligomeric compounds in cranberry products. The method relied on robust, simple, and inexpensive instrumental equipment present in most of routine analytical laboratories. Sample extracts in methanol/water/hydrochloric...
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Validation and Regulatory Issues for Sample Preparation
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Introductory Chapter: Evolution of Sample Preparation
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Introductory Chapter: Evolution of Sample Preparation
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Size-exclusion chromatography for the determination of the boiling point distribution of high-boiling petroleum fractions
PublicationThe paper describes a new procedure for the determination of boiling point distribution of high-boiling petroleum fractions using size exclusion chromatography with refractive index detector. Thus far, the determination of boiling range distribution by chromatography has been accomplished using simulated distillation with gas chromatography with the flame ionization detection. This study revealed that in spite of substantial differences...
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Sample preparation techniques for determination of pesticide residues in food samples
PublicationPesticides are very important in increasing the efficiency and quality of agricultural production. They are applied in many spheres of life, not only in agriculture, and their applications are expanding. Despite their numerous merits, pesticides are some of the most toxic substances contaminating our environment and have a negative impact on the human health. Properties of pesticides such as stability, ability to bioaccumulation...
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New Trends in Sample Preparation Techniques for the Analysis of the Residues of Pharmaceuticals in Environmental Samples
PublicationPharmaceutical residues in the environment is a field of special interest due to the adverse effects to either human health or aquatic and soil environment. Pharmaceuticals have been already detected in underground, surface and wastewaters, soils, manure and sediments. The growing awareness of environmental pollution arising from human activity forces the need for their comprehensive determination. Environmental samples are complex...
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Dynamic Headspace Sampling as an Initial Step for Sample Preparation in Chromatographic Analysis
PublicationThis work represents a brief summary of the use of dynamic headspace (DHS) as a technique for sample preparation in chromatographic analysis. Despite numerous developments in the area of analyte isolation and enrichment, DHS remains one of the fundamental methods used with GC. In our opinion, interest in this technique will not diminish significantly because it conforms to stipulations of green analytical chemistry. Moreover, DHS...
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Variable Ratio Sample Rate Conversion Based on Fractional Delay Filter
PublicationIn this paper a sample rate conversion algorithm which allows for continuously changing resampling ratio has been presented. The proposed implementation is based on a variable fractional delay filter which is implemented by means of a Farrow structure. Coefficients of this structure are computed on the basis of fractional delay filters which are designed using the offset window method. The proposed approach allows us to freely...
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An experimental assessment on a diesel engine powered by blends of waste-plastic-derived pyrolysis oil with diesel
PublicationThe utilization of plastic solid wastes for sustainable energy production is a crucial aspect of the circular economy. This study focuses on pyrolysis as an effective method to convert this feedstock into renewable drop-in fuel. To achieve this, it is essential to have a comprehensive understanding of feedstock composition, pyrolysis process parameters, and the physicochemical characteristics of the resulting fuel, all correlated...
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Spectroscopic Optical Coherence Tomography for Thin Layer and Foil Measurements
PublicationThe main goal of this research was to assess if it is possible to evaluate the thickness of thin layers (both thin films on the surface and thin layers below the surface of the tested object) and foils using optical coherence tomography (OCT) for thickness assessment under the resolution of the standard commercially available OCT measurement system. In the proposed solution, light backscattered from the evaluated thin layer has...
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Normal-form preemption sequences for an open problem in scheduling theory
PublicationStructural properties of optimal preemptive schedules have been studied in a number of recent papers with a primary focus on two structural parameters: the minimum number of preemptions necessary, and a tight lower bound on shifts, i.e., the sizes of intervals bounded by the times created by preemptions, job starts, or completions. These two parameters have been investigated for a large class of preemptive scheduling problems,...