Filtry
wszystkich: 4766
wybranych: 3859
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: DEVULCANIZATION CONDITIONS
-
A simple approach to heat exchanger sizing optimisation by means of entrophy generation minimisation
PublikacjaIn 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...
-
Plasticity of Bead-On-Plate Welds Made with the Use of Stored Flux-Cored Wires for Offshore Applications
PublikacjaExtreme atmospheric conditions in the marine and offshore industry are harmful to engineering materials, especially to welded joints, and may cause degradation of their properties. This article presents the results of research on the plasticity of bead-on-plate welds made using two types of seamless, copper plated flux-cored wires. Before welding, spools with wire were stored for 1 month in two distinct locations with different...
-
Overheating of underground power cable line due to its partial exposition to solar radiation
PublikacjaCurrent-carrying capacity of underground power cable lines depends, among others, on thermal resistivity of the soil and cables layout: trefoil formation, flat formation with or without spacing. If conditions for heat transfer in the ground are favorable, the current-carrying capacity is relatively high. Therefore, it generates risk of the power cables overheating, if part of the cable line is located vertically in the air, to...
-
Optymalizacja długości krzywych przejściowych przy budowie i modernizacji linii kolejowych
PublikacjaW drogach szynowych przy obliczaniu długości krzywych przejściowych analizowane są jedynie warunki na ich długość minimalną. Odmienna sytuacja występuje przy projektowaniu dróg, gdzie rozpatrywane są też warunki na długość maksymalną. Spośród nich szczególną rangę ma warunek poprawności geometrycznej układu. W artykule zawarto jego adaptację do specyfiki trasy kolejowej. Sformułowano cel optymalizacji przy obliczaniu długości krzywej...
-
A video monitoring system using ontology-driven identification of threats
PublikacjaIn this paper, we present a video monitoring systemthat leverages image recognition and ontological reasoningabout threats. In the solution, an image processing subsystemuses video recording of a monitored area and recognizesknown concepts in scenes. Then, a reasoning subsystem uses anontological description of security conditions and informationfrom image recognition to check if a violation of a conditionhas occurred. If a threat...
-
Computational modelling of historic masonry railroad arch bridges
PublikacjaThe problems encountered during the analyzes of structural response of historic masonry railroad arch bridges are described in this paper. The attention is mainly focused on the stiffness of the masonry arches, their strengths and appropriate estimation of railroad load intensity. Issues related to computational modelling of two, existing, almost 130 years old masonry arch railroad bridges are presented in this context. The main...
-
Legal and Economic Conditions of the Creating and Activity of Entrepreneursin Poland. VATT Governement Inst. Econ. Res. C**2002 [nr] 290 s. 153- 162 bibliogr. 10 poz. Discussion papers. Workshopon Studies for Nordther. Kalastajatorrpa,30-31 May 2002.Prawne i ekonomiczne uwarunkowania działalności przedsiębiorców w Polsce.
PublikacjaW artykule przedstawiono warunki prawne, które muszą być spełnione przyuruchamianiu działalności gospodarczej w Polsce. Wskazano również co sprzyjai co hamuje rozwój działalności przedsiębiorców w naszym kraju.
-
Technical diagnostics and monitoring of traction current collectors
PublikacjaNew evaluation methods of the technical condition of rolling stock current collectors are proposed in this paper. The method of automatic measurement of the pantograph static force characteristic, realized when the vehicle runs through the test section of the track with especially prepared overhead line height distribution, has been practically implemented by the Polish Railways. The method of testing the slipper spring suspension...
-
Validation of atmospheric aerosols parallel sampling in a multifold device
PublikacjaIn this work, particulate matter was collected using an active sampling system consisting of a PM10 (<10 μm) inlet coupled to a multifold device containing six channels, connected to a vacuum pump. Each channel was equipped with a filter holder fitted with adequately chosen filters. The system was fixed on a metallic structure, which was placed on the roof of the laboratory building, at the Faculty of Sciences, in Lisbon. Sampling...
-
Lighting requirements for pedestrian crossings - positive contrast
PublikacjaFor many years now in Poland there has been a large number of road accidents at pedestrian crossings during night periods [5, 11]. One of the technical solutions that can improve this condition is the use of proper lighting for pedestrian crossings. The designated pedestrian crossing should be visible in different weather conditions and at different times of the day. In case of night vision restrictions use artificial lighting...
-
Design and numerical testing of 5-box gfrp shell footbridge
PublikacjaThe paper formulates new design conditions for composite footbridges, taking into account the material and structural specificity of these objects, i.e. the strength condition, the serviceability condition and the frequency condition. A GFRP composite footbridge labelled with CFB2 code has been designed, with the original superstructure in the form of an opened-closed 5-box girder. The foot and cycle track bridge is simply supported,...
-
Tribo-Environment Dependent Chemical Modification of Sliding Interfaces in Ultrananocrystalline Diamond Nanowall Film: A Correlation with Friction and Wear
PublikacjaTribological properties of ultrananocrystalline diamond nanowall (UNCD NW) films were investigated quantitatively in three different and controlled tribo-environmental conditions, proposing the passivation and graphitization mechanisms. However, these mechanisms are rather complicated and possibly can be understood in well-controlled tribological conditions. It was shown that the friction and wear of these films were high in highPage 1...
-
LOS and NLOS identification in real indoor environment using deep learning approach
PublikacjaVisibility conditions between antennas, i.e. Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) can be crucial in the context of indoor localization, for which detecting the NLOS condition and further correcting constant position estimation errors or allocating resources can reduce the negative influence of multipath propagation on wireless communication and positioning. In this paper a deep learning (DL) model to classify LOS/NLOS...
-
Bernstein-type theorem for ϕ-Laplacian
PublikacjaIn this paper we obtain a solution to the second-order boundary value problem of the form \frac{d}{dt}\varPhi'(\dot{u})=f(t,u,\dot{u}), t\in [0,1], u\colon \mathbb {R}\to \mathbb {R} with Sturm–Liouville boundary conditions, where \varPhi\colon \mathbb {R}\to \mathbb {R} is a strictly convex, differentiable function and f\colon[0,1]\times \mathbb {R}\times \mathbb {R}\to \mathbb {R} is continuous and satisfies a suitable growth...
-
Modelling of spirometry - the application for diagnostic purposes
PublikacjaThe process of the tissue oxygen supply is the fundamental process of the human life. The lung functioning consists of three processes: the ventilation, the perfusion and the diffusion. The paper deals with one of these processes which is the ventilation process. The quality of the pulmonary ventilation has a strong influence on the patient's health condition. Numerous limitations are imposed on conditions of the lung quality measurement,...
-
Magnetic Field Generated by Short Circuit Current in the 110 kV Power System
PublikacjaElectric fields within tissues induced by magnetic fields including transients or short-term peaks should not be time averaged and be regarded as instantaneous values as established in the ICNIRP (International Commission on Non - Ionizing Radiation Protection) guidelines. Measurements of power lines magnetic fields with regard to human beings exposure are carried out typically with maximum current load at current balance condition...
-
A bound on the number of middle-stage crossbars in f-cast rearrangeable Clos networks
PublikacjaIn 2006 Chen and Hwang gave a necessary and sufficient condition under which a three-stage Clos network is rearrangeable for broadcast connections. Assuming that only crossbars of the first stage have no fan-out property, we give similar conditions for f-cast Clos networks, where f is an arbitrary but fixed invariant of the network. Such assumptions are valid for some practical switching systems, e.g. high-speed crossconnects....
-
Damage detection in a bolted lap joint using guided waves
PublikacjaThe paper presents the experimental investigation of guided waves application to the condition assessment of prestressed bolted connections and a concept of new quantitative indicator. The main goal of the research was the analysis of the influence of the contact conditions changes to the characteristics of a propagating disturbance. The experimental tests were carried out for a single bolted lap joint. The excitation and acquisition...
-
Impact of Propeller Emergence on Hull, Propeller, Engine, and Fuel Consumption Performance in Regular Head Waves
PublikacjaIn this study, the impact of propeller emergence on the performance of a ship (speed), propeller (thrust, torque, and RPM), a diesel engine (torque and RPM) and fuel consumption are analysed under severe sea conditions. The goal is to describe the variation in the system variables and fuel consumption rather than analysing the motion of the ship or the phenomenon of propeller ventilation in itself. A mathematical model of the...
-
Diagnosing marine turbine engines through energy characteristics of their flow section
PublikacjaThe aim of the performed research was to develop of diagnostic method of the flow section of a marine turbine combustion engine based on the level of delamination of its energy characteristics. The here adopted diagnostic model provides for a formulation of the evaluation of the technical conditions based on the measurements of the parameters of the thermodynamic medium in the characteristic control cross-sections of the engine...
-
Searching for road deformations using mobile laser scanning
PublikacjaMillions of people use roads every day all over the world. Roads, like many other structures, have an estimated durability. In Poland a lot of the roads were built at the turn of the 20th and 21st c., especially for light cars. Many of these roads carry traffic and heavy goods vehicles which were not predicted when the traffic was first estimated. It creates a lot of problems with technical conditions and the infrastructure must...
-
3D Machine Vision System for Inspection of Contact Strips in Railway Vehicle Current Collectors
PublikacjaConstruction and technical condition of current collectors is crucial to reliability and safety of railway transportation. According to the Technical Specifications for Interoperability railway vehicles in the European Union should be equipped with carbon contact strips. Excessive wear or defects of contact strips degrade the capability of undisturbed power transmission, cause faster wear of contact wire, and can even result in...
-
Exhaust gas temperature measurements in diagnostics of turbocharged marine internal combustion engines. Part I. Standard measurements.
PublikacjaThe article discusses the problem of diagnostic informativeness of exhaust gas temperature measurements in turbocharged marine internal combustion engines. Theoretical principles of the process of exhaust gas flow in turbocharger inlet channels are analysed in its dynamic and energetic aspects. Diagnostic parameters are defined which enable to formulate general evaluation of technical condition of the engine based on standard...
-
STUDY ON THE RELATIONSHIP BETWEEN VEHICLE MAINTENANCE AND FUEL CONSUMPTION
PublikacjaA contemporary road vehicle (RV) is a rather complex system, consisting of a large number of subsystems, assemblies, units, and elements (parts). While operating, an RV interacts with the environment, and its elements interact with each other. Consequently, the properties (parameters) of these elements change in the process - hardness, roughness, size, relative position, gapping, etc. A partial solution to the presented problems...
-
A pilot study to assess manufacturing processes using selected point measures of vibroacoustic signals generated on a multitasking machine
PublikacjaThe article presents the method for the evaluation of selected manufacturing processes using the analysis of vibration and sound signals. This method is based on the use of sensors installed outside the machining zone, allowing to be used quickly and reliably in real production conditions. The article contains a developed measurement methodology based on the specific location of microphones and vibration transducers mounted on...
-
Nonprotein nitrogenous compounds
PublikacjaThe non-protein nitrogen (NPN) fraction is an important group of food components for both technological and nutritional reasons. Free amino acids (FAAs), oligopeptides, amines, nucleic acids, and nucleotides, as well as other low-molecular nitrogen-containing components (cyanogenic glycosides, alkaloids, thiazoles, oxazoles, pyrroles, and pyrazines), are found in most foods. Their content depends on many factors, starting from...
-
Wulkanizaty kauczuku naturalnego otrzymane z użyciem plastyfikatorów pochodzenia roślinnego
PublikacjaCelem niniejszej pracy było zbadanie wpływu epoksydowanych olejów roślinnych na wybrane właściwości wul-kanizatów kauczuku naturalnego. Jako plastyfikatorów użyto epoksydowanego oleju sojowego oraz epoksydo-wanego oleju palmowego. Wpływ olejów naturalnych porównano także z wulkanizatami przygotowanymi bez użycia zmiękczaczy, jak i zawierającymi olej maszynowy, pochodzący z przerobu ropy naftowej. Zbadano wpływ rodzaju...
-
Nitrogen fraction fluctuation during wastewater treatment in a multistage treatment wetland
PublikacjaAlthough the size of pollutants discharged to a WWTP plays an important and often underestimated role in characterizing treat ability and hence the degree of contaminant removal of wastewater. From one hend In order to obtain efficient nitrogen removal in thedenitrification process, sufficient amounts of bioavailable carbon source should be ensured bur for the other hand in TWs, particulates from the wastewater are naturally trapped...
-
DETERMINANTS OF INLAND NAVIGATION ON THE VISTULA FROM WARSAW TO GDAŃSK
PublikacjaWaterborne transport is the cheapest, the safest and the least harmful to the natural environment. Restoring regular waterway cargo transport will require revitalisation of the existing trans-shipment and logistics infrastructure for commercial inland ports and building new. Transport policy makers must remember that waterborne transport is the most ecological type of transport. It produces only 10% of the gases emitted to the...
-
Numerical investigation on dynamic response of a steel lattice tower under various seismic events
PublikacjaThe present paper presents the results of the numerical study designed to investigate the soil-structure flexibility effects on modal parameters (i.e. fundamental frequencies) and time-history analysis response (represented by the top relative displacements) of a 46.8 m high steel lattice tower subjected to a number of ground motions including also one mining tremor. In addition to the fixed-base condition, three different soil...
-
The Influence of Storage on Human Milk Lipidome Stability for Lipidomic Studies
PublikacjaHuman milk (HM) lipidome stability during storage is crucial in lipidomic studies to avoid misinterpretations. Facing the lack of comprehensive work on the HM lipidome stability, we performed a study on a potential alteration in the lipid profiles of HM samples stored under different conditions. An untargeted LC-Q-TOF-MS-based approach was applied to study the influence of storage conditions as well as the interaction of the storage...
-
ANALIZA STANU TECHNICZNEGO RUROCIĄGÓW: WODY PRZeMYSŁOWEJ I SOLANKI
PublikacjaPracę wykonano na zlecenie Przedsiębiorstwa Badawczo-Wdrożeniowego "HYDRO-POMP" Sp. z o.o. ul. Wróblewskiego 19, 93-578 Łódź. Wykonawcą zlecenia jest Politechnika Gdańska, Wydział Chemiczny, Katedra Elektrochemii, Korozji i Inżynierii Materiałowej, 80-233 Gdańsk, ul. G. Narutowicza 11/12. Celem pracy była analiza stanu technicznego i badania dwóch rurociągów: solanki oraz wody przemysłowej. Badania wykonywano w warunkach terenowych...
-
Nowa metoda diagnostyki stanu technicznego nakładek stykowych
PublikacjaThe current collection system, which consists of the overhead contact line and a current collector, is particularly important in electric rail vehicles, where their reliability is concerned. Faultless current collection is conditioned not only by suitable construction of these elements but also by their proper maintenance. Retaining permanent electrical contact is essential in DC systems, where current demand is relatively high. In...
-
Effect of bio-based components on the chemical structure, thermal stability and mechanical properties of green thermoplastic polyurethane elastomers
PublikacjaIt seems to be obvious that conditions changes during polyols synthesis have impact on the polyols properties. Even the chemical formula is the same or similar, physicochemical properties and also molecular weight of polyols might be different and are significant in term of future polyurethanes properties and processing. In this work, fully bio-based poly(propylene succinate)s synthesized at different temperature conditions were...
-
Computing algebraic transfer entropy and coupling directions via transcripts
PublikacjaMost random processes studied in nonlinear time series analysis take values on sets endowed with a group structure, e.g., the real and rational numbers, and the integers. This fact allows to associate with each pair of group elements a third element, called their transcript, which is defined as the product of the second element in the pair times the first one. The transfer entropy of two such processes is called algebraic transfer...
-
A method to synthesise groove cam Geneva mechanisms with increased dwell period
PublikacjaThe 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...
-
Curve Curvature Analysis of a Grain Trajectories in Variable Honing of Cylindrical Holes of Thin Wall Cylinder Liners as a Honing Process Optimization Strategy
PublikacjaThe main problem of honing of thin wall cylinder liners is a thermal distortion of honed holes. The higher the value of the temperature of the honed workpiece, the greater its holes deformation. The paper presents a method of reducing the temperature occurring in the honing process as a result of the application of a variable honing kinematics conditions with particular emphasis on the analysis of the effect of the value of the...
-
Generalized regression neural network and fitness dependent optimization: Application to energy harvesting of centralized TEG systems
PublikacjaThe thermoelectric generator (TEG) system has attracted extensive attention because of its applications in centralized solar heat utilization and recoverable heat energy. The operating efficiency of the TEG system is highly affected by operating conditions. In a series-parallel structure, due to diverse temperature differences, the TEG modules show non-linear performance. Due to the non-uniform temperature distribution (NUTD) condition,...
-
Processing, physico-mechanical and thermal properties of reclaimed GTR and NBR/reclaimed GTR blends as function of various additives
PublikacjaIn this work, ground tire rubber (GTR) was mechano-chemically reclaimed in the presence of bitumen and various additives. During studies three types of processing and curing additives: (i) peptizer P300; (ii) vulcanization accelerator tetramethylthiuram disulfide (TMTD) and (iii) organic peroxide di(2-tert-butyl-peroxyisopropyl)benzene (BIB1) were applied to enhance reclaiming of GTR. Reclaiming process was evaluated by oscillating...
-
Noise and Rolling Resistance Properties of Various Types of Winter Tyres Compared to Normal Car Tyres
PublikacjaTo cope with winter weather conditions, potentially including snow and ice, it is common to use winter tyres, or ”all-seasons” tyres assumed to be safe both in summer and winter. In some northern countries, winter tyres are mandatory. Traditionally, it has been assumed that winter tyres are noisier than normal tyres (here called summer tyres) and winter tyres equipped with studs are assumed to be very noisy.This paper presents...
-
ANALYSIS OF THE IMPACT OF THE PLANNED SEWAGE DISCHARGE FROM THE ‘NORTH’ POWER PLANT ON THE VISTULA WATER QUALITY
PublikacjaThe paper presents results of analysis of the industrial sewage discharge impact from the ‘North’ Power Plant on the Vistula water quality around 45+330 of the river kilometer. For the analysis, the two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined....
-
Development of the System Assurance Reference Model for Generating Modular Assurance Cases
PublikacjaAssurance cases are structured arguments used to demonstrate specific system properties such as safety or security. They are used in many industrial sectors including automotive, aviation and medical devices. Larger assurance cases are usually divided into modules to manage the complexity and distribute the work. Each of the modules is developed to address specific goals allocated to the specific objects i.e. components of the...
-
Selection of Organic Coating Systems for Corrosion Protection of Industrial Equipment
PublikacjaThe most important element of corrosion protection in industrial conditions is the protective coating system. However, selecting the right coating can often be a real problem due to the sheer number of coating manufacturers and their products on the market. A quantitative approach based on the data mining technique used to analyze the obtained multi-site exposure data has been proposed. This was demonstrated by the example of the...
-
Badanie stanu nawierzchni drogowej z wykorzystaniem uczenia maszynowego
PublikacjaW artykule opisano budowę systemu informowania o stanie nawierzchni drogowej z wykorzystaniem metod cyfrowego przetwarzania obrazów oraz uczenia maszynowego. Efektem wykonanych prac badawczych jest eksperymentalna platforma, pozwalająca na rejestrację uszkodzeń na drogach, system do analizy, przetwarzania i klasyfikacji danych oraz webowa aplikacja użytkownika do przeglądu stanu nawierzchni w wybranej lokalizacji.
-
Stability by linear approximation for time scale dynamical systems
PublikacjaWe study systems on time scales that are generalizations of classical differential or difference equations and appear in numerical methods. In this paper we consider linear systems and their small nonlinear perturbations. In terms of time scales and of eigenvalues of matrices we formulate conditions, sufficient for stability by linear approximation. For non-periodic time scales we use techniques of central upper Lyapunov exponents...
-
Effect of annealing temperature on slurry erosion resistance of ferritic X10CrAlSi18 steel
PublikacjaIn the present work, the slurry erosion tests were carried out to investigate the influence of heat treatment on slurry erosion process of ferritic X10CrAlSi18 stainless steel using a slurry pot test rig. X10CrAlSi18 stainless steel was tested in as-received condition and after annealing at three different temperatures: 600°C, 800°C and 1000°C. Degradation of materials due to slurry erosion depends on many factors connected with...
-
Efficiency of thermomechanical reclaiming of ground tire rubber conducted in counter-rotating and co-rotating twin screw extruder
PublikacjaIn this article the results of research on a continuous thermomechanical reclaiming process of ground tire rubber (GTR) conducted in a twin screw extruder are presented. The effects of the rotation direction (co-rotating/counter-rotating), design of co-rotating plasticizing units and the rotational speed of the screws on the extruder working parameters, sol fraction and the degree of reclaiming in the obtained products were described....
-
Modeling of lapping plate wear and conditioning in single-sided lapping
PublikacjaIn order to achieve higher quality on worked surfaces with lower roughness, very high accuracy of shape and dimensions it is crucial to improve conventional finishing technologies and to develop new working principles. Single-sided lapping is one of the most effective planarization technologies and it is determined by a number of factors and boundary conditions. The most significant influence over a dimensional and profile accuracy,...
-
Determination of t8/5 cooling times for underwater local dry welding of steel
PublikacjaKnowledge of thermal history is the basic condition for studying the structure - properties of welded joints. The determinant of thermal history is the thermal cycle, whose in-situ measurements are still a big challenge. Water as the welding environment complicates this issue even more. The article presents a method to determine an equation for calculating t8/5 cooling times for underwater gas metal arc welding of unalloyed steels...
-
Compatibility of Crude Oil Blends─Processing Issues Related to Asphaltene Precipitation, Methods of Instability Prediction─A Review
PublikacjaProcessing crude oil of variable composition, especially due to the need to process crude oil blends obtained from various sources, presents a tremendous process challenge. This is mainly due to the destabilization of the colloidal system manifested mostly by the precipitation of the asphaltene fraction. The precipitation of asphaltenes from crude oil is a serious problem during extraction, transport, and processing. In the latter...