Filters
total: 1136
filtered: 1054
displaying 1000 best results Help
Search results for: MAXIMUM AXLE LOADS
-
Differential-algebraic systems with maxima
PublicationMetoda numeryczno-analityczna została zastosowana do układów równań różniczkowo-algebraicznych z operatorem maximum. Zakładając warunek Lipschitza na funkcje występujące w zagadnieniu pokazano, że ciąg iteracji prostych jest zbieżny do rozwiązania zagadnienia pomocniczego. Podano warunki dostateczne na istnienie rozwiązania problemu wyjściowego. Iteracje Seidla też były przedmiotem badań. W ostatniej części pracy był dyskutowany...
-
Biomechanics of the front abdominal wall as a potential factorleading to recurrence with laparoscopic ventral hernia repair
PublicationThis study investigated the front abdominal wallto describe its elasticity in vivo and searched for elongationsthat possibly stretched an implanted mesh, therebycausing fixation failure and subsequent recurrence.To measure front abdominal wall elongations, amodel of fascia movements was created. Eight healthyvolunteers were measured during exercise to determine theextent of elongations in their front abdominal wall. Videoswere...
-
A simple approach to heat exchanger sizing optimisation by means of entrophy generation minimisation
PublicationIn the paper an attempt is presented to find the method of optimization of microtube diameter with respect to optimal thermal-hydraulic conditions in the single-phase shell-and-tube heat exchangers. The approach is based on consideration of pumping power at the condition of maximum heat transfer by the heat exchanger tube system. In the optimization method the tube diameter is first specified and then appropriate calculations are...
-
Weldability of S460ML High Strength Low Alloy Steel in Underwater Conditions
PublicationThe paper presents experimental evaluation of susceptibility of the high strength S460ML steel to cold cracking in the conditions of wet welding with the use of covered electrodes. From the results of Tekken tests it was found out that the investigated steel was characterised, in the conditions of the carried out experiments (underwater wet welding and air welding with rutile electrodes), of high susceptibility to cold cracking....
-
Fluoroaromatic substituents attached to carbon nanotubes help to increase oxygen concentration on biocathode in biosensors and biofuel cells
PublicationBased on the known ability of perfluorodecalin/perfluorohydrocarbons to enhance oxygen solubility we modified oxygen sensitive biocathode by adding perfluorinated components to the catholite. This procedure improved the efficiency of the oxygen sensitive cathodes. Glassy carbon electrodes covered with single-wall carbon nanotubes (SWCNTs) with covalently bonded perfluoroaromatic groups were shown to be more sensitive to oxygen,...
-
Engineering TADF, Mechanochromism, and Second Harmonic Up- conversion Properties in Regioisomeric Substitution Space
PublicationThis research article explores the distinct TADF efficiency of three donor-acceptor based regio-isomers: DPAOCN (ortho- isomer), DPAMCN (meta-isomer), and DPAPCN (para-isomer). DPAPCN exhibits maximum TADF efficiency in both solution and solid-state with an impressive reverse inter-system crossing (RISC) rate of ~ 106 s-1; the underlying cause being the minimum singlet-triplet splitting energy or ∆EST and maximum SOC (spin-orbit...
-
Modeling and Accuracy Assessment of Determining the Coastline Course Using Geodetic, Photogrammetric and Satellite Measurement Methods: Case Study in Gdynia Beach in Poland
PublicationThe coastal environment represents a resource from both a natural and economic point of view, but it is subject to continuous transformations due to climate change, human activities, and natural risks. Remote sensing techniques have enormous potential in monitoring coastal areas. However, one of the main tasks is accurately identifying the boundary between waterbodies such as oceans, seas, lakes or rivers, and the land surface....
-
Influence of the Addition of Recycled Aggregates and Polymer Fibers on the Properties of Pervious Concrete
PublicationThe aim of the study was to check the possibility of reusing aggregate from recycled concrete waste and rubber granules from car tires as partial substitution of natural aggregate. The main objective was to investigate the effects of recycled waste aggregate modified with polymer fibers on the compressive and flexural strength, modulus of elasticity and permeability of pervious concrete. Fibers with a multifilament structure and...
-
A novel cold-active β-D-galactosidase with transglycosylation activity from the Antarctic Arthrobacter sp. 32cB - gene cloning, purification and characterization
PublicationA gene encoding a novel β-D-galactosidase from the psychrotolerant Antarctic bacterium Arthrobacter sp. 32cB was isolated, cloned and expressed in Escherichia coli. The active form of recombinant β-D-galactosidase consists of two subunits with a combined molecular weight of approximately 257 kDa. The enzyme's maximum activity towards o-nitrophenyl-β-D-galactopyranoside was determined as occurring at 28 °C and pH 8.0. However, it...
-
The protocol for using elastic wall model in modeling blood flow within human artery
PublicationMedical diagnostic tools will play a major role in the future for an effective patient treatment and reduction their mortality, related to the cardiovascular system diseases (CVDs). There is an urgent need for developing diagnostic procedure to be robust, reliable, accurate and efficient, in the framework of a paradigm shift. Application of numerical techniques is seen as a perspective tool for such purpose. Nevertheless, existing...
-
Parametric study of fluid flow and heat transfer over louvered fins of air heat pump evaporator
PublicationTwo-dimensional numerical investigations of the fluid flow and heat transfer have been carried out for the laminar flow of the louvered fin-plate heat exchanger, designed to work as an air-source heat pump evap- orator. The transferred heat and the pressure drop predicted by simulation have been compared with the corresponding experimental data taken from the literature. Two dimensional analyses of the louvered fins with varying...
-
Design and Analysis of Artificial Neural Network (ANN) Models for Achieving Self-Sustainability in Sanitation
PublicationThe present study investigates the potential of using fecal ash as an adsorbent and demonstrates a self-sustaining, optimized approach for urea recovery from wastewater streams. Fecal ash was prepared by heating synthetic feces to 500 °C and then processing it as an adsorbent for urea adsorption from synthetic urine. Since this adsorption approach based on fecal ash is a promising alternative for wastewater treatment, it increases...
-
Dynamic analysis of temporary steel grandstand equipped with different types of bracing system
PublicationIn the paper, behaviour of a temporary steel grandstand equipped with two different types of bracing system has been analysed through the numerical study. A typical solution concerning application of a diagonal tubular members has been compared with elements proposed by authors and called polymer dampers. A polymer element consists of two L-shape steel members bonded with polymer mass. The aim of the paper is to verify the effectiveness...
-
Rigid finite elements and multibody modeling in analyses of a robot shaped elastic/plastic deformations of a beam
PublicationDynamics analysis of a system composed of a parallel manipulator and of an elastic beam is presented in the paper. Classic 3RRR parallel manipulator is considered and used to deform the beam. Elasto-plastic deformations are investigated. Rigid-finite-elements technique is employed to deal with dynamics of the beam. A multibody structure is associated with the introduced hybrid system in order to model its dynamics. Idea of the...
-
The impact of material degradation on the resistance and reliability of truss structures
PublicationThe paper analyses limit load-carrying capacity and buckling load of truss towers used to support high voltage power lines. The analysed typical structure was subjected to characteristic loads and their combinations. The results were applied to assess structural resistance with regard to steel corrosion in the long-term operation. The extent of structural deterioration was assessed due to Young's modulus decrement in the course...
-
A multi-agent method for periodicity detection in distributed events
PublicationMulti-agent systems working in constantly changing environments may be challenged by instantaneous unavailability of their autonomous agents caused e.g. by limited computing resources. A new method of self-organization of distributed service components is proposed, suitable for multi-agent systems. This method relies on particular agents carrying out separate analyzes of their individual processing loads or other specific events....
-
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...
-
Influence of sludge treatment processes on heavy metal speciation
PublicationSludge composition is depending on sewage quality and also affected by processing methods such as thickening, stabilization and dewatering. During those processes some of sludge's undesirable properties might be reduced or enhanced.The objective of the study is the assessment of the influence of sludge processing on selected heavy metals partitioning between phases (aqueous and particle) and sludge. Sludge from the WWTP in Gdansk...
-
The use of weight in motion data to heavy vehicles - pavement interaction analysis
PublicationWeight in motion (WIM) is the element of modern intelligent transport systems created to control commercial vehicles and to detect overloaded items. Because all of the vehicles crossing the WIM station are weighed and recognized, given data can be used to vehicle-pavement interaction analysis. The paper presents the results of analysis based on data from seven WIM stations localized in Motorway and National Roads in Poland. The...
-
Response of a steel tank during earthquakes and mining tremors - experimental investigation
PublicationCylindrical steel tanks are very popular shell structures used to store the products of chemical and petroleum industries. Any failure might have disastrous consequences, therefore their safety and reliability is essential. Earthquakes are the most dangerous and also the most unpredictable dynamic loads acting on such structures. On the other hand, mining tremors are usually considered to be less severe due to lower acceleration...
-
Probabilistic sensitivity of limit states of structures. The Monte Carlo simulation
PublicationDesign sensitivity deals with the variation of structural response, implicitly dependent on the design variables of the problem. An attempt is made to implement probabilistic notation in engineering sensitivity analysis. The procedure to implement the sensitivity of a structural limit state to a given basic variable is described in the paper - its main idea, depicted by a flowchart and numerical examples of engineering analysis....
-
The Influence of External Additional Loading on the Muscle Activity and Ground Reaction Forces during Gait
PublicationAsymmetrical external loading acting on the usculoskeletal system is generally considered unhealthy. Despite this knowledge, carrying loads in an asymmetrical manner like carrying on one shoulder, with one hand, or on the strap across the torso is a common practice. This study is aimed at presenting the effects of the mentioned load carrying methods on muscle activity assessed by using thermal field and ground reaction forces....
-
RESEARCH ON HYDRODYNAMIC PEEK JOURNAL BEARINGS LUBRICATED WITH WATER AND OIL
PublicationThe main purpose of the research was to determine the possibilities and experimentally test the benefits of replacing conventional oil lubrication with ecological water lubrication. Tests were carried out on a test rig for hydrodynamic radial bearings under conditions representative of the expected applications for the bearing in water turbines. Bearings made from the polymer material PEEK (polyether ether ketone) were tested under static...
-
Buckling of simplified models of silo with corrugated walls and vertical stiffeners
PublicationThe paper deals with buckling of cylindrical silos composed of corrugated sheets and vertical stiffeners (columns). Comprehensive finite element analyses were carried out for a perfect silo by means of a linear buckling approach. Corrugated walls were simulated as an equivalent orthotropic shell and vertical thin-walled columns as beam elements. Calculations for perfect silos with different numbers of columns made it possible to...
-
Multi-objective optimization for assessment of topological modification in UWB antennas
PublicationThis paper addresses an issue of systematic and rigorous assessment of effects of topological modifications on the performance of compact UWB antennas. Application of fast surrogate-assisted multi-objective optimization procedures allows us for obtaining, in a practically acceptable timeframe, a set of designs representing the best possible trade-offs between conflicting objectives (here, antenna size minimization and reduction...
-
Stability and load bearing capacity of a truss with elastic braces
PublicationThe present paper is devoted to the numerical and experimental investigations of stability of a truss stiffened by elastic braces. The model of a real roof truss scaled by factor ¼ was investigated. In the research the linear buckling and non-linear static analysis of the truss shell and beam model with geometric and material non-linearity is presented. The initial imperfections were assumed in the form of the first buckling mode....
-
The influence of small amount of substances present in tissue on the optical spectrum of immunosuppressive drug
PublicationIn this paper, we describe how commonly present in tissue substances - sodium chloride and glucose - affect the optical spectrum of an immunosuppressive drug (Cyclaid® by Apotex). Prepared samples were investigated using the spectrophotometer in the spectrum range from 250 nm to 1100 nm. The maximum wavelength shift calculated on the basis of measurement results is not bigger than the measurement wavelength step. So, it can be...
-
Impact of radio wave polarisation on off-body communications in indoor environments
PublicationThis paper describes the measurements and the analysis of the impact of radio wave polarisation on off-body communications in Body Area Networks in indoor environments. Measurements on polarisation impact are briefly described. Five investigated scenarios with different body postures and different antenna placements are characterised. The difference between the vertical and horizontal components of the received radio signal are...
-
Numerical Study on Mitigation of Flow Maldistribution in Parallel Microchannel Heat Sink: Channels Variable Width Versus Variable Height Approach
PublicationMicrochannel heat sink on one hand enjoys benefits of intensified several folds heat transfer performance but on the other hand has to suffer aggravated form of trifling limitations associated with imperfect hydrodynamics and heat transfer behavior. Flow maldistribution is one of such limitation that exaggerates temperature nonuniformity across parallel microchannels leading to increase in maximum base temperature. Recently, variable...
-
Modeling the pH effects on nitrogen removal in the anammox-enriched granular sludge
PublicationThe aim of the study was to determine the pH effects on nitrogen removal in the anammox-enriched granular sludge. The experimental data were extracted from a 4L completely-mixed batch reactor with the granular sludge at different initial pH values (6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5) and constant temperature T=30℃. Simulations were run in GPS-X 6.4 using a comprehensive mechanistic model Mantis2. Two kinetic parameters, including...
-
On the hat problem on a graph
PublicationThe topic of this paper is the hat problem in which each of n players is uniformly and independently fitted with a blue or red hat. Then everybody can try to guess simultaneously his own hat color by looking at the hat colors of the other players. The team wins if at least one player guesses his hat color correctly, and no one guesses his hat color wrong; otherwise the team loses. The aim is to maximize the probability of winning....
-
Modeling by finite element methods of impact of erosion on frequency of normal modes of L-0 blade
PublicationAfter some time of exploitation steam turbine rotors blades in energetic industry they are being eroded and also their frequency of normal modes is changed. Those changes can cause to unwanted shift of blades normal mode frequencies. It is necessary to find quick method of rating changes of frequency in connection of mass loss due erosion. The evaluation of this dependence was made by finite element modeling method using HyperWorks...
-
Multi Parameter Sliding Test Result Evaluation for The Selection of Material Pair for Wear Resistant Components of a Hydraulic motor Dedicated for Use With Environmentally Friendly Working Fluids
PublicationIn the paper the method and results are presented of the testing of tribological performance of a number of hard materials available commercially. The tests consisted in unidirectional sliding with liquid lubrication. The load and velocity regime chosen were similar to a standard four-ball lubricity test with constant velocity and load increasing over time. The regime was modified in such a way that over the initial part of the...
-
MODELING THE pH EFFECTS ON NITROGEN REMOVAL IN THE ANAMMOX-ENRICHED GRANULAR SLUDGE
PublicationThe aim of the study was to determine the pH effects on nitrogen removal in the anammox-enriched 10 granular sludge. The experimental data were extracted from a 4L completely-mixed batch reactor with the 11 granular sludge at different initial pH values (6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5) and constant temperature 12 T=30℃. Simulations were run in GPS-X 6.4 using a comprehensive mechanistic model Mantis2. Two 13 kinetic parameters,...
-
Mitigating the seismic pounding of multi-story buildings in series using linear and nonlinear fluid viscous dampers
PublicationSeismic-induced pounding between adjacent buildings may have serious consequences, ranging from minor damage up to total collapse. Therefore, researchers try to mitigate the pounding problem using different methods, such as coupling the adjacent buildings with stiff beams, connecting them by using viscoelastic links, and installing damping devices in each building individually. In the current paper, the effect of using linear and...
-
Thermo-Mechanical Simulation of Underwater Friction Stir Welding of Low Carbon Steel
PublicationThis article investigates the flow of materials and weld formation during underwater friction stir welding (UFSW) of low carbon steel. A thermo-mechanical model is used to understand the relation between frictional heat phenomena during the welding and weld properties. To better understand the effects of the water environment, the simulation and experimental results were compared with the sample prepared by the traditional friction...
-
ZARZADZANIE ORGANIZACJĄ TYPU SMART
PublicationZaprezentowano organizacji, w której charakterystykę wpisano następujące cechy: strategiczne uwarunkowanie, maksymalną innowacyjność, atrakcyjność dla interesariuszy, rozwijanie osobowości pracowników oraz twórczość w działaniu. Te atrybuty, tworzą koncepcję organizacji SMART (akronim od pierwszych liter powyższych cech), która wyróżnia się dodatkowo strukturą opartą o dynamicznie kreowane zespoły oraz skutecznym wspomaganiem...
-
Sprzętowa implementacja transformacji Hougha w czasie rzeczywistym
PublicationW artykule przedstawiono implementację sprzętową w FPGA algorytmu do wykrywania kształtów aproksymowanych zbiorem linii prostych podczas przetwarzania obrazu cyfrowego w czasie rzeczywistym. W opracowanej strukturze sprzętowej podniesiono efektywność przetwarzania poprzez zastosowanie przetwarzania przepływowego, lookup table, wykorzystanie wyłącznie arytmetyki liczb całkowitych oraz rozproszenie pamięci głosowania. Eksperymentalnie...
-
Electrical and structural properties of Nb-doped SrTiO3
PublicationNiobium-doped strontium titanate synthesized via conventional solid-state reaction has been studied. Influence of niobium content on the lattice parameters and electrical conductivity has been reported. Various reduction conditions have been investigated. For samples reduced in hydrogen at 1400°C, a transition from thermally activated to metallic behavior has been observed. Maximum electrical conductivity (ca. 55 Scm−1 at 650°C)...
-
Badanie sprawności algorytmów szeregowania danych w systemie WiMAX Mobile
PublicationW pracy przedstawiono wyniki badań symulacyj-nych różnych metod szeregowania danych i przydziału podnośnych w sieciach opartych na standardzie IEEE 802.16e (WiMAX Mobile). W pracy zostały opisane najważniejsze mechanizmy odpowiedzialne za zarządza-nie jakością usług w tych sieciach. Analizę porównaw-czą przeprowadzono dla następujących metod: Round Robin (RR), Proportional Fairness (PF) oraz Maximum Rate (MR). Znaczną uwagę poświęcono...
-
ANALIZA EFEKTYWNOŚCI METOD GŁĘBOKIEGO UCZENIA W ODBIORZE SYGNAŁÓW GMSK
PublicationSztuczna inteligencja odnajduje coraz szersze zastosowanie we współczesnej radiokomunikacji, choć głównie w ujęciu badawczym. Niniejszy artykuł przedstawia przegląd i ewaluację metod z obszaru głębokiego uczenia umożliwiających detekcję sygnałów z modulacją GMSK (ang. Gaussian Minimum Shift Keying) w kanale AWGN. Badane modele porównane zostały z optymalnym detektorem pracującym zgodnie z regułą największej wiarygodności MLSE (ang....
-
POSSIBILITY OF IDENTIFICATION OF TECHNICAL CONDITION OF BEARINGS FOR SELF-IGNITION ENGINES BY APPLICATION OF ACOUSTIC EMISSION AS A DIAGNOSTIC SIGNAL
PublicationThis paper presents the results of empirical studies where the acoustic emission (AE) method was applied to identify the technical condition of sliding surfaces of main and crank bearings for main diesel engines. The test results indicate that the measurements of the AE parameters allow the technical condition identification for bearings of this type. The results refer to the measurements of the parameters for AE generated in the...
-
Arylated carbon nanotubes for biobatteries and biofuel cells
PublicationSinglwalled carbon nanotubes (swcnts)covalently phenylated, napthylated or terphenylated were used for the construction of cathodes in a biobattery and in a biofuel cell. zn is the anode in the biobaterry and single-walled carbon nanotubes are covalently modified with glucose oxidase/catalase (swcnt-gox/cat) and the biofuel cell anode. the cell parameters were determined and the potentials of each of the electrodes under cell working...
-
Alternative diagnostic method applied on marine diesel engines having limited monitoring susceptibility
PublicationThe paper presents a method of technical state evaluation of working spaces of a marine diesel engine at the limited control susceptibility. The method foresees making a diagnosis of the engine's working spaces on the basis of measurements of the exhaust gas pressure in the channels connecting engine cylinders with the turbocharger's turbine. Diagnostic measurements are carried out at representative (comparative) steady loads depending...
-
Sensitivity analysis of free torsional vibration frequencies of thin-walled laminated beams under axial load
PublicationThe paper addresses sensitivity analysis of free torsional vibration frequencies of thin-walled beams of bisymmetric open cross-section made of unidirectional fibre-reinforced laminate. The warping effect and the axial end load are taken into account. The consideration is based upon the classical theory of thin-walled beams of non-deformable cross-section. The first-order sensitivity variation of the frequencies is derived with...
-
Effective configuration of a double triad planar parallel manipulator for precise positioning of heavy details during their assembling process
PublicationIn the paper, dynamics analysis of a parallel manipulator is presented. It is an atypical manipulator, devoted to help in assembling of heavy industrial constructions. Few atypical properties are required: small workspace; slow velocities; high loads. Initially, a short discussion about definition of the parallel manipulators is presented, as well as the sketch of the proposed structure. In parallel, some definitions, assumptions...
-
An Intergrated Model of Motion, Steering, Positioning and Stabilization of an Unmanned Autonomous Maritime Vehicle
PublicationIn the paper the aim of an interdisciplinary research is presented. The research method is introduced. An object the unmanned autonomous maritime vehicle is briefly described. The key research problem concerns a combined model of the vehicle motion including the loads of lift and hydrodynamic nature. The model takes into account the gravity and displacement forces, resistance and thrust forces, lift and other hydrodynamic forces....
-
Effect of Pendolino high-speed rail on the structure of buildings located the proximity of the railway tracks
PublicationThe following research focuses on the dynamic analysis of the impact of the high-speed train inducted vibrations on the structures located near railway tracks. The office complex chosen as the subject of calculations is located in the northern part of Poland, in Gdańsk, in the proximity of Pendolino, the high speed train route. The high speed trains are the response for the growing needs for more efficient railway system. However...
-
Case Study of Old Steel Riveted Railway Truss Bridge: From Material Characterization to Structural Analysis
PublicationThe structural analysis of an old steel riveted railway truss bridge located over the Maruska River on the Działdowo – Olsztyn, Poland railway line is performed in this paper to check its behaviour under today’s railway loads. The mechanical properties of construction steel extracted from the old steel bridge are investigated by tensile tests, impact tests through the Charpy pendulum impact V-notch, and an optical emission spectrometer....
-
Comparative tests of the wall thickness effect of a glass-reinforced thermosetting plastic coating with a non-circular cross section in a soil-coating object for economic aspect
PublicationCulvert structures made of plastics are employed extensively in the construction of new facilities as well as the renovation of existing ones. Due to the high costs of materials required for the manufacturing of these goods, the objective of this research is focused to lessen the thickness of the walls, which may, on the other hand, result in a reduction in the stiffness of the system. In the course of the testing, the structure...