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Wyniki wyszukiwania dla: fractions of heavy metals
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A screening of select toxic and essential elements and persistent organic pollutants in the fur of Svalbard reindeer
PublikacjaReindeers play an important role in the polar ecosystem, being long-lived sole vegetarians feeding on local vegetation. They can be used as a valuable bioindicator, helping us to understand contaminants’ impact on the polar terrestrial ecosystem. Still, scarce data exist from research in which polar herbivores (especially those from the European parts of the Arctic) were a major study subject for trace elements and persistent organic...
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Bridging the gap between business process models and use-case models
PublikacjaToday's software development methodologies are equipped with a plethora of methods and techniques for business process engineering and Requirements Engineering. However, heavy investments in IT have not brought forth expected results. What seems to be lacking is a systematic approach that consolidates both disciplines to gain a synergistic effect. To address this challenge we extend Use-Case Driven Approach (UCDA) by binding use...
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Analysis of the possibility of determining the general characteristics using the operational data of a vehicle engine
PublikacjaThe paper presents an analysis of the possibility of determining the general characteristics using the operational data of an engine of refuse collection vehicle. Data acquisition was done by reading information from the CAN network using FMS standard (Fleet Management System), which is widely used in heavy duty vehicles since year 2002. The paper presents the analysis of the expected measurement uncertainties resulting from the...
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Safety of erection and repair of steel tanks with geometric imperfections using heavylift jack-up system
PublikacjaSafety analysis is performed of cylindrical vertical steel tanks during erection using heavylift jack up system. During an assembly or repair process a set of hydraulic supports is used. It allows to use the in-place lifting of heavy steel constructions on the required height. Wind can strongly influence stability of the lifted tank. Any geometric imperfections can reduce the critical or limit load. In the work failures of the...
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ANALYSIS OF THE INCREASE OF CONSTRUCTION COSTS IN URBAN REGENERATION PROJECTS
PublikacjaThe subject of this paper is the analysis and evaluation of the reasons for construction costs increases in urban regeneration projects. The analysis considers major refurbishments of real estates’, as well as heavy repair and modernization of the road system. For the period mentioned, the costs from works and expenditure schedules were compared with the costs of additional works, which shows the percentage cost increase in relation...
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Mercury in Living Organisms: Sources and Forms of Occurrence, Bioaccumulation, and Determination Methods
PublikacjaMercury (Hg) is a heavy metal with well-known and broadly tested toxicity. Since Hg pollution and its impacts on human health are of global concern, it has become necessary to develop analytical methodologies that will provide tools to obtain reliable analytical information about the levels of Hg in samples, which very often have a complex matrix composition. This chapter summarizes key information on Hg and its chemical forms,...
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On noncausal identification of nonstationary stochastic systems
PublikacjaIn this paper we consider the problem of noncausal identification of nonstationary,linear stochastic systems, i.e., identification based on prerecorded input/output data. We show how several competing weighted least squares parameter smoothers, differing in memory settings, can be combined together to yield a better and more reliable smoothing algorithm. The resulting parallel estimation scheme automatically adjusts its smoothing...
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Hybrid all-cellulose reinforcement in polypropylene matrix biocomposites for injection moulding - influence of particle geometry and volume fraction on hybrid effect
PublikacjaThe presented study is focused on evaluation of influence of reinforcement volume fraction and geometry on the occurrence of positive hybrid effect by the hybridisation of man-made cellulose fibres (rayon viscose) with cellulose microparticle fillers applied in polypropylene matrix. Four volume fractions of reinforcement were used at 1:1 combination of short man-made cellulose fibres with cellulose microfillers of different aspect...
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Wpływ mikrosfer-frakcji odpadów paleniskowych na mikrostrukturę i wybrane właściwości uzytkowe
PublikacjaIn this study, the microspheres samples were collected from national power station „Dolna Odra”. In this study, the following materials were used: Portland cement class 32,5R and aggregates of 2-8 and 8-16 fractions and natural sand with a maximum grain size of 2 mm and water. Concrete mixtures were made with microspheres additions of 15%, 25% and 40%. A constant water to binder ratio (w/b) of 0,52 was used throughout the investigation....
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Spetiation of organic matter in Vertical Flow Constructed Wetlands
PublikacjaThe object of the research were VFCWs which are a component of biological treatment of two hybrid hydrophyte systems located in Wieszyno and Wiklino, close to Słupsk, Poland. The facilities that are subject to analyses are unified in terms of structure (filtration material, depth of the bed and time of operation), but they differ in organic matter load, amounting respectively to: 8.0 gCOD/m2day and 31.0 gCOD/m2day.The intensity...
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Dynamic Research of Masonry Vault in a Technical Scale
PublikacjaThe paper presents preliminary results of dynamic tests of the masonry barrel vault in a technical scale. Experimental studies are intended to identify material properties of homogenized masonry vaults under dynamic loads. The aim of the work is to create numerical models to analyse vault’s dynamic response to dynamic loads in a simplest and accurate way. The process of building the vault in a technical scale is presented in the...
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Recovery of Valuable Materials and Methods for Their Management When Recycling Thin-Film CdTe Photovoltaic Modules
PublikacjaDue to the development of new photovoltaic technologies, there is a need to research new recycling methods for these new materials. The recovery of metals from photovoltaic (PV) modules would reduce the consumption of raw materials. Therefore, the development of recycling technologies for used and damaged modules of newer generations is important for environmental reasons. The aim of the research is to shed light on the nature...
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Optimizing the computation of a parallel 3D finite difference algorithm for graphics processing units
PublikacjaThis paper explores the possibilities of using a graphics processing unit for complex 3D finite difference computation via MUSTA‐FORCE and WENO algorithms. We propose a novel algorithm based on the new properties of CUDA surface memory optimized for 2D spatial locality and compare it with 3D stencil computations carried out via shared memory, which is currently considered to be the best approach. A case study was performed for...
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Allergic reactions as a defense of the organism to the influence of implants components made of stainless steel
PublikacjaDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...
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Allergic Reactions as a Defense of the Organism to the Influence of Implants Components Made of Stainless Steel
PublikacjaDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...
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Application of Barkhausen effect in the impact assessment of welding to internal stress distribution in steel
PublikacjaThe paper presents identification method of internal stresses in plane steel elements in the chase of deliverance and welding assembly. The assessment was made by means of a non-destructive experimental method based on measurements incorporating local external magnetic field and the measurement of induced voltage, including Barkhausen noise. This method allows a degradation assessment due to internal and external actions, causing...
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Application of Barkhausen effect in the impact assessment of welding to internal stress distribution in steel
PublikacjaThe paper presents identification method of internal stresses in plane steel elements in the chase of deliverance and welding assembly. The assessment was made by means of a non-destructive experimental method based on measurements incorporating local external magnetic field and the measurement of induced voltage, including Barkhausen noise. This method allows a degradation assessment due to internal and external actions, causing...
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The effect of the exposure-in-oil on the contact of the polymers forming sliding layers in hydrodynamic bearings. Wpływ ekspozycji w oleju na kąt zwilżania polimerów stosowanych na warstwy ślizgowe w łożyskach hydrodynamicznych.
PublikacjaPolimery stosowane jako warstwy ślizgowe w hydrodynamicznych łożyskach wzdłużnych to zazwyczaj tworzywa termoplastyczne charakteryzujące się relatywnie wysokimi wartościami kątów zwilżania w porównaniu z metalami. Metale, w tym również Babbitt czy inne stopy łożyskowe, cechują niskie wartości kątów zwilżania. Im niższy kąt, tym powierzchnia lepiej się zwilża. Tworzywa sztuczne wykorzystywane w węzłach tribologicznych mających zapewnić...
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Hydrothermal modification of TiO2 nanotubes in water and alkali metal electrolytes (LiNO3, NaNO3, KNO3) – Direct evidence for photocatalytic activity enhancement
PublikacjaThe influence of hydrothermal annealing (HA) of TiO2 nanotubes (TiO2-NTs) in various baths (H2O, LiNO3, NaNO3, KNO3 performed for 4 h, 24 h, 64 h), on their photocatalytic and photoelectrocatalytic properties, was studied. The use of electrolytes was to enable the monitoring of photoactivity changes as a result of the expected impact on the population of hydroxyl groups on the surface. The assumption turned out to be correct and...
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ZnO-decorated green-synthesized multi-doped carbon dots from Chlorella pyrenoidosa for sustainable photocatalytic carbamazepine degradation
PublikacjaThe promising green synthesis of carbon dots (CDs) from microalga Chlorella pyrenoidosa was achieved using simple hydrothermal and microwave-assisted methods. Doping of nanomaterials by nonmetals (N, S, and P) was confirmed by X-ray photoelectron spectroscopy (XPS), while the existence of metals in the CDs was confirmed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and transmission electron microscopy (TEM),...
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The Hydrolysis of Slowly Biodegradable Substrate in Activated Sludge
PublikacjaIn a present work a novel procedure, based on the standard batch tests and pretreatment of wastewater sample with coagulation-flocculation method, was proposed to evaluate the effects of hydrolysis of slowly biodegradable substrate (Xs) on biological nutrient removal (BNR) processes in activated sludge systems. The study was conducted at two large BNR wastewater treatment plants (WWTPs) in northern Poland: "Wschod" in Gdansk and...
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An improved scalable method of isolating asphaltenes
PublikacjaA new, improved and scalable procedure of asphaltene fraction isolation is presented and compared to standard test methods. The new procedure uses 1:40 feedstock to solvent (n-heptane) ratio (g/mL), filtration through a cellulosic thimble and extensive washing in a Soxhlet type extractor. The group type composition and purity of the asphaltene fractions have been examined using thin-layer chromatography with flame-ionization detection....
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Hydrogen production from biomass using dark fermentation
PublikacjaHydrogen applicability in the power, chemical and petrochemical industries is constantly growing. Efficientmethods of hydrogen generation from renewable sources, including waste products, are currently being de-veloped, even though hydrogen is mainly produced through steam reforming or thermal cracking of natural gasor petroleum fractions. In paper alternative methods of hydrogen production with a particular emphasis on darkfermentation...
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Ancient settlements-atavistic solutions for present water supply and drainage problems engendered by urbanism
PublikacjaWater is the most valuable resource available on earth. Although it is present in abundance, its usable volume is very scarce. This is the reason behind the existence of both floods and droughts around the world. However, human settlements face water scarcity issues that are primarily engendered by improper town planning measures. To create a balance between the available fractions of water, it is therefore imperative to have proper...
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State equations in the mathematical model of dynamic behaviour of multihull floating unit
PublikacjaPrzedstawiony artykuł dotyczy dynamiki wielokadłubowej jednostki pływającej typu katamaran poddanej wymuszeniom pochodzącym od falowania nieregularnego. Analiza dynamiki jednostki wielokadłubowej została przeprowadzona przy założeniu, że model układu jest modelem liniowym na który działa fala nieregularna. Model matematyczny takiego układu dynamicznego jest reprezentowany poprzez równania stanu. Zapisane zostały równania uwzględniające...
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Deep compaction control of sandy soils
PublikacjaVibroflotation, vibratory compaction, micro-blasting or heavy tamping are typical improvement methods for the cohesionless deposits of high thickness. The complex mechanism of deep soil compaction is related to void ratio decrease with grain rearrangements, lateral stress increase, prestressing effect of certain number of load cycles, water pressure dissipation, aging and other effects. Calibration chamber based interpretation...
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Towards Knowledge Sharing Oriented Adaptive Control
PublikacjaIn this paper, we propose a knowledge sharing oriented approach to enable a robot to reuse other robots' knowledge by adapting itself to the inverse dynamics model of the knowledge-sharing robot. The purpose of this work is to remove the heavy fine-tuning procedure required before using a new robot for a task via reusing other robots' knowledge. We use the Neural Knowledge DNA (NK-DNA) to help robots gain empirical knowledge and...
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Comparative Study of Machining Technology Selection to Manufacture Large-Size Components of Offshore Constructions
PublikacjaThe focus of this paper is on process planning for large parts manufacture in systems of definite process capabilities, involving the use of multi-axis machining centres. The analysis of machining heavy mechanical components used in off-shore constructions has been carried out. Setup concepts applied and operation sequences determined in related process plans underwent studies. The paper presents in particular a reasoning approach...
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A Family of Pb-based Superconductors with Variable Cubic to Hexagonal Packing
PublikacjaWe describe three previously unreported superconductors, BaPb3, Ba0.89Sr0.11Pb3, and Ba0.5Sr0.5Pb3. These three materials, together with SrPb3, form a distinctive isoelectronic family of intermetallic superconductors based on the stacking of Pb planes, with crystal structures that display a hexagonal to cubic perovskite-like progression, as rarely seen in metals. The superconducting transition temperatures (Tc) are similar for...
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Birds' feathers – Suitable samples for determination of environmental pollutants
PublikacjaThe intensive development of industry and human population results in large amounts of different xenobiotic emitted into individual ecosystem components. As a consequence, monitoring of the level of pollution of particular elements of the environment by exotoxins has become a common interest. The determination of environmental changes by different types of biological indicators is called bioindication, which is used as one of the...
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Polaron hopping conduction in manganese borosilicate glass
PublikacjaA study on a novel material - manganese borosilicate glass without alkali metals, was reported. It was found that the obtained samples containing high amount of manganese oxide (60MnO–xSiO2–(40 − x)B2O3, x = 5, 10, 15, 20 and 30 mol%) were amorphous and homogeneous. XPS measurements showed that most of manganese ions are at oxidation level of Mn2 + ions and the mean oxidation level slightly moves toward higher value, with increasing...
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Długie pociągi
PublikacjaWskazano, że przy wprowadzaniu długich pociągów pojawiają się możliwości, ale i ograniczenia różnej natury oraz problemy do rozwiązania. Inne w przypadku długich pociągów i inne w przypadku ciężkich pociągów. Pokazano długie pociągi, jako szansę na polepszenie bezpieczeństwa na drogach, poprzez ograniczenie na nich ruchu samochodów ciężarowych. Łatwiej będzie w praktyce realizować pomysł „Tiry na tory” Długie pociągi są szansą...
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Novel Diazocrowns with Pyrrole Residue as Lead(II) Colorimetric Probes
PublikacjaNovel 18- and 23-membered diazomacrocycles were obtained with satisfactory yields by diazocoupling of aromatic diamines with pyrrole in reactions carried under high dilution conditions. X-ray structure of macrocycle bearing five carbon atoms linkage was determined and described. Compounds were characterized as chromogenic heavy metal ions receptors. Selective color and spectral response for lead(II) was found in acetonitrile and...
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An application of acoustic sensors for the monitoring of road traffic
PublikacjaAssessment of road traffic parameters for the developed intelligent speed limit setting decision system constitutes the subject addressed in the paper. Current traffic conditions providing vital data source for the calculation of the locally fitted speed limits are assessed employing an economical embedded platform placed at the roadside. The use of the developed platform employing a low-powered processing unit with a set of microphones,...
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An innovative method of measuring the extension of the piston rod in hydraulic cylinders, especially large ones used in the shipbuilding and offshore industry
PublikacjaThe article presents the results of selected works related to the wider subject of research conducted at the Faculty of Mechanical Engineering and Shipbuilding at the Gdańsk University of Technology, regarding designing various on board devices with hydraulic drive for ships and other offshore facilities. One of the commonly used these mechanisms are hydraulic actuators with the measurement of the piston rod extension. The issue...
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Distribution and bioavailability of mercury in the surface sediments of the Baltic Sea
PublikacjaThe study aimed to determine the level of mercury (Hg) and its labile and stable forms in the surface sediments of the Baltic Sea. The work considers the impact of current and historical sources of Hg on sediment pollution, together with the influence of different environmental parameters, including water inflows from the North Sea. Surface sediments (top 5 cm) were collected in 2016–2017 at 91 stations located in different...
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MOBILITY OF SHALE DRILL CUTTINGS CONSTITUENTS
PublikacjaThis study focuses on the abundance and mobility of metals and trace elements from shale drill cuttings into the water, being the main component of hydraulic fracturing fluid. The relationship between composition of the shale rock and the potential element release during standard water-based leaching tests was characterized by means of X-Ray Fluorescence spectroscopy (XRF). The XRF analysis confirmed the assumption of shales constituents...
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Mathematical modeling and prediction of pit to crack transition under cyclic thermal load using artificial neural network
PublikacjaThe formation of pitting is a major problem in most metals, which is caused by extremely localized corrosion that creates small holes in metal and subsequently, it changes into cracks under mechanical load, thermo-mechanical stress, and corrosion process factors. This research aims to study pit to crack transition phenomenon of steel boiler heat tubes under cyclic thermal load, and mathematical modeling...
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Treated wasetewater as a source of humic substances in surface waters
PublikacjaHumic substances impose substantial effect on the aquatic environment as well as the water organisms and human health. Among other features, the humic acids determine organoleptic properties of surface waters. Therefore explanation of the origin and properties of humic acids in surface waters is one of the priorities of water technology.Recently it was pointed out that in the wastewater treatment process organic compounds characterized...
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Uptake, accumulation, and translocation of Zn, Cu, Pb, Cd, Ni, and Cr by P. australis seedlings in an urban dredged sediment mesocosm: impact of seedling origin and initial trace metal content
PublikacjaThe study presents results from 6 months of phytoremediation of sediments dredged from three urban retention tanks carried out in a mesocosm setup with the use of P. australis. Two kinds of P. australis seedlings were considered: seedlings originating from natural (uncontaminated - Suncont) and anthropogenically changed environments (contaminated – Scont); this distinction was reflected in the baseline concentrations of trace metals...
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Profiling and Qualitative Assessment of Enzymatically and Thermally Oxidized Egg Yolk Phospholipids using a Two‐Step High‐Performance Liquid Chromatography Protocol
PublikacjaA two‐step high‐performance liquid chromatography (HPLC) method for the profiling and qualitative assessment of oxidized phospholipids (oxPL) present in foods was developed. The applicability of the investigated two‐step HPLC protocol was verified for separation of enzymatically and thermally oxidized hen egg yolk phospholipids (PL) as a relevant food model. In the first step, seven individual PL classes were separated using hydrophilic...
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ENVIRONMENTAL DEGRADATION OF DISSIMILAR AUSTENITIC 316L AND DUPLEX 2205 STAINLESS STEELS WELDED JOINTS
PublikacjaThe paper describes structure and properties of dissimilar stainless steels welded joints between duplex 2205 and austenitic 316L steels. Investigations were focused on environmentally assisted cracking of welded joints. The susceptibility to stress corrosion cracking (SCC) and hydrogen embrittlement was determined in slow strain rate tests (SSRT) with the strain rate of 2.2 × 10–6 s–1. Chloride-inducted SCC was determined in the...
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Contamination of Runoff Water at Gdańsk Airport (Poland) by Polycyclic Aromatic Hydrocarbons (PAHs) and Polychlorinated Biphenyls (PCBs)
PublikacjaAirport runoff can contain high concentrations of various pollutants, in particular polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), the environmental levels of which have to be monitored. Airport runoff water samples, collected at the Gdańsk-Rębiechowo Airport from 2008 to 2009, were analysed for PAHs and PCBs by gas chromatography. The aromatic fractions were separated by liquid-liquid extraction...
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Effective Drug Concentration and Selectivity Depends on Fraction of Primitive Cells
PublikacjaPoor efficiency of chemotherapeutics in the eradication of Cancer Stem Cells (CSCs) has been driving the search for more active and specific compounds. In this work, we show how cell density-dependent stage culture profiles can be used in drug development workflows to achieve more robust drug activity (IC50 and EC50) results. Using flow cytometry and light microscopy, we characterized the cytological stage profiles of the HL-60-,...
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Noncentrosymmetric superconductor with a bulk three-dimensional Dirac cone gapped by strong spin-orbit coupling
PublikacjaThe layered, noncentrosymmetric heavy element PbTaSe2 is found to be superconducting. We report its electronic properties accompanied by electronic-structure calculations. Specific heat, electrical resistivity, and magnetic-susceptibility measurements indicate that PbTaSe2 is a moderately coupled, type-IIBCSsuperconductor (Tc = 3.72 K, Ginzburg–Landau parameter κ = 17) with an electron-phonon coupling constant of λep = 0.74. Electronic-structure...
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Traffic-induced vibrations. The impact on buildings and people
PublikacjaTraffic-induced vibrations have recently been of major concern to engineers as one of the aspects of so called physical environmental pollution. The interest is related to the observations of serious negative effects of such kind of vibrations on buildings and their inhabitants. Traffic-induced vibrations may cause plaster cracks, structural damage and even failure and collapse of the structure. They may also be the reason of serious...
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Design of a test bench for determining the general characteristics of an internal combustion engine using a hydraulic power take-off system
PublikacjaThe paper presents a design of an engine test bench, which is used to determine the general characteristics of a truck engine using a power take-off (PTO). PTO drives a hydraulic system that generates a load on the engine at various points in its operation in the power range specified by the hydraulic system. The design allows for stationary and mobile tests with the test bench mounted on the truck, without any modification of...
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Scaled agile framework. Dealing with software process‐related challenges of a financial group with the action research approach
PublikacjaThis article reports on a domain-specific software development venture at Nordea. We explore organizational constraints, challenges, and corrective actions undertaken when scaling the agile development approach of their Core Banking Platform program. The fit and required customizations of the rather complex and rigid SAFe framework in a policy-heavy financial institution are audited against the organic growth of the program. In...
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Analysis and design improvement of high class roads’ arched sections in Poland
PublikacjaAlthough Polish road network standards, in particular higher classes of roads are improving dynamically the number of fatalities on the network is still higher that EU’s average. Ensuring road safety and high maintaining standards is a complex issue and one that poses a major challenge for all road authorities. Road accidents at high speed roads characterize specially serious material and social consequences, thus research into...
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Dirac fermions and possible weak antilocalization in LaCuSb2
PublikacjaLayered heavy-metal square-lattice compounds have recently emerged as potential Dirac fermion materials due to bonding within those sublattices. We report quantum transport and spectroscopic data on the layered Sb square-lattice material LaCuSb2. Linearly dispersing band crossings, necessary to generate Dirac fermions, are experimentally observed in the electronic band structure observed using angle-resolved photoemission spectroscopy,...