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Search results for: DOUBLE-STAGE YIELD BUCKLING-RESTRAINED BRACE STEEL SLIT DAMPER EXPERIMENTAL VALIDATION CYCLIC LOADING TEST NOVEL BRACING SYSTEM SEISMIC RETROFIT ENERGY DISSIPATION DEVICES
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Modeling of wood frame structures with different insulation materials under damaging dynamic loading
PublicationWood frame buildings are very popular in regions that are exposed to different dynamic excitations, such as damaging earthquakes. Their seismic resistance is really important in order to prevent structural damages and human losses. This paper presents the results of advanced numerical investigation carried out using the FEM. Based on the models of wall panels, the numerical model of real structure of the wood frame building has...
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Battery Technologies in Electric Vehicles: Improvements in Electric Battery Packs
PublicationRestrictions on fossil fuels and related environmental pollution issues motivate many organizations and countries to set their focus on electric vehicles (EVs) rather than conventional internal combustion engine vehicles [1], [2]. EVs require an energy storage system to store converted electric power in another form of energy and then reconvert the stored energy to electric power whenever it is required. The energy stored can be...
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Degradation of 1,4-dioxane by sono-activated persulfates for water and wastewater treatment applications
PublicationThis paper presents a hybrid advanced oxidation process (AOP) based on sonocavitational activation of persulfate (PS) for degradation of 1,4-dioxane during wastewater treatment. Application of sono-cavitation effectively convert PS to radical species demonstrating synergistic effect by increasing the reaction rate and reducing the required energy for activation. It is economically feasible and deployed alternative to the direct...
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Innovative Implantable Left Ventricular Assist Device—Performance under Various Resistances and Operating Frequency Conditions
PublicationThis paper presents the operation of an innovative left ventricular assist device under various resistances and operating frequencies. The operating principle of the device is based on pulsatile blood flow, which is forced by a suction–discharge device pumping helium into a set of intra-cardiac balloons. In this way, the ejection fraction of the left ventricle is increased, and the mitral valve is additionally occluded. What is...
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A model of liquid film breakdown formed due to impingement of a two-phase jet on a horizontal surface
PublicationThe present work aims to provide an explanation to the phenomenon of breakdown of the thin liquid film created by impinging two-phase, liquid-gas jet. Existing in the literature models describe merely thebreakdown of single phase liquid films. The model presented here is based on examination of mass and energy equations under the applied criterion of the minimum of total energy. That allows to determinethe minimum thickness of...
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Trends in Locally Balanced Energy Systems without the Use of Fossil Fuels: A Review
PublicationIn recent years, the idea of the operation of energy systems (power systems, heating systems) has changed significantly. This paper is an overview of locally balanced energy systems without the use of fossil fuels. The paper justifies the concept of local energy balancing in a new energy system that does not use fossil fuels (coal, natural gas, and crude oil), based on European Union guidelines and formal documents as well as the...
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Rheological, Mechanical, Microstructural and Radiation Shielding Properties of Cement Pastes Containing Magnetite (Fe3O4) Nanoparticles
PublicationThis work examines the influence of iron oxide nanoparticles (Fe3O4 NPs) on neutron and gamma-ray radiation shielding characteristics of Portland cement paste. Experimental evaluations were supplemented with theoretical studies using NXCom program. Portland cement pastes with 5, 10, 15, 20, and 30 wt% of nanomagnetite cement replacement were produced. Moreover, rheological, early strength development, compressive strength, and...
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Speed Sensorless AC Drive with Inverter LC Filter and Fault Detection Using Load Torque Signal
PublicationThe industrial development in recent years has seen a major increase in the use of induction motors, whereby the cost has to be as low as possible and the lifetime as long as possible. To follow up this desire, investigations in this area have become very intense. For that reason, this paper presents a solution for driving an induction motor and simultaneous fault detection with no need for additional sensors. In order to achieve...
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Nonlinear numerical simulation of earthquake-induced pounding between timber frame buildings
PublicationEarthquakes may induce serious dynamic loads acting on buildings, which can lead to damage or even destruction of the whole structure. In densely populated areas, it is quite common that buildings are located very close one to another which can result in pounding between them during ground motions. Due to the environmental awareness, multi-story timber frame buildings are gaining popularity and therefore there is a need to investigate...
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Application of Stirling Engine Type Alpha Powered by the Recovery Energy on Vessels
PublicationThe Stirling engine is a device, in which thermal energy is transformed into mechanical without a contact between the heat carrier, and the working gas closed in the engine. Mentioned feature makes this type of engine very attractive for the use of the recovery energy, taken from other heat devices. One of the potential applications of Stirling engines is the use of thermal energy generated in the ship's engine room for producing...
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On the application of magnetoelastic properties measureme nts for plastic level determination in martensitic steels
PublicationThe change in the dislocation density, induced by plastic deformation, influences strongly the magnetic domain structure inside the material. Being so, classic parameters, like the coercivity or magnetic permeability, can be a good measure of the deformation level, yet their reliable determination in a non-destructive way in industrial environment is problematic. The magnetoacoustic emission (MAE) which results from the non-180...
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Oversizing the photovoltaic generator capacity in a micro photovoltaic plant
PublicationA significant part of photovoltaic micro installations in Poland is characterized by photovoltaic generator oversizing in relation to the inverter. The idea of oversizing, however, still raises doubts among some plant owners. In the paper, the energy yield of installation with an oversized and not oversized photovoltaic generator is presented on selected examples, showing the legitimacy of oversizing.
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Influence of Properties of Hydraulic Fluid on Pressure Peaks in Axial Piston Pumps’ Chambers
PublicationThe article concentrates on the research of the pressure peaks in a working chamber of an axial piston pump. The main focus of the article is the influence of fluid properties on the pressure peaks value. Experimental and analytical methods were used to determine the impact of the fluid density, viscosity, compressibility and aeration. The article describes the pressure peak generation process and explains the theoretical basis...
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Transparent nanocomposite coatings based on epoxy and layered double hydroxide: Nonisothermal cure kinetics and viscoelastic behavior assessments
PublicationLayered double hydroxide (LDH) has a particular place in clay family because of its flame retardant action. The nanoplatelet-like structure of LDH makes possible development of polymer composites with cationic or anionic nature structures in which macromolecules are positioned in between nanoplatelet galleries. In this work, neat epoxy and its transparent nanocomposite coatings with sodium dodecylbenzene sulfonate (SDBS)-modified...
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Alternative way of the main reinforcement anchorage in reinforced short cantilevers
PublicationThe results of the experimental investigation of the reinforced corbels and dapped end beams with steel studs were introduced in the work. The efficiency of this type of the reinforcement was compared with the typical reinforcenet applied in reinforced conctrete construcions.
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A low complexity double-talk detector based on the signal envelope
PublicationA new algorithm for double-talk detection, intended for use in the acoustic echo canceller for voice communication applications, is proposed. The communication system developed by the authors required the use of a double-talk detection algorithm with low complexity and good accuracy. The authors propose an approach to doubletalk detection based on the signal envelopes. For each of three signals: the far-end speech, the microphone...
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Some Aspects of Designing Nozzle Segments of Axial Microturbines,
PublicationIn the paper a multi-stage micro-turbine with partial admission of all the stages is described in detail and the results of the numerical calculations and experimental investigations are presented, followed by an appropriate discussion and conclusions.
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Validation of Services Supporting Healthcare Standards Conformance
PublicationThe paper presents the results of experimental validation of a set of innovative software services supporting processes of achieving, assessing and maintaining conformance with standards and regulations. The study involved several hospitals implementing the Accreditation Standard promoted by the Polish Ministry of Health. First we introduce NOR-STA services that implement the TRUST-IT methodology of argument management. Then we...
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Efficient Method for the Synthesis of Functionalized Basic Maleimides
PublicationA three-step procedure involving Diels-Alder condensation of maleic anhydride with furane, formation of N-substituted imide upon reaction with appropriate diamine and a final retro Diels-Alder regeneration of the maleic carbon-carbon double bond is proposed for an unequivocal synthesis of N-substituted basic maleimides. The novel method is characterized by mild reaction conditions, easy work-up, high yields and no need for additional...
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Cyclic behaviour modelling of additively manufactured Ti-6Al-4V lattice structures
PublicationThe present work is concerned with the numerical modelling of the cyclic behaviour of Ti-6Al-4V lattice structures. In the study, diamond structures of titanium alloy produced by the additive laser powder bed fusion (LPBF) method with different degrees of relative density were used. Realistic geometric models of the studied mesostructures were generated using computed microtomography, taking into account the imperfections of the...
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PROBLEMS OF THE STARTING AND OPERATING OF HYDRAULIC COMPONENTS AND SYSTEMS IN LOW AMBIENT TEMPERATURE (PART IV) MODELLING THE HEATING PROCESS AND DETERMINING THE SERVICEABILITY OF HYDRAULIC COMPONENTS DURING THE STARTING-UP IN LOW AMBIENT TEMPERATURE
PublicationDesigners of hydraulically driven machines and devices are obliged to ensure during design process their high service life with taking into account their operational conditions. Some of the machines may be started in low ambient temperature and even in thermal shock conditions (due to delivering hot working medium to cold components). In order to put such devices into operation appropriate investigations, including experimental...
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Evaluation of excessive noise effects on hearing employing psychoacoustic dosimetry
PublicationResearch results regarding the noise impact on hearing applying the concept of the Psychoacoustic Noise Dosimetry (PND) are presented. The general characteristics of the PND algorithm are discussed. Additionally, the results of hearing examinations conducted in the laboratory conditions are shown. The main objective of the research was to determine the time needed for the Temporary Threshold Shift to reverse. The results were used...
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Domain segmentation for low-cost surrogate-assisted multi-objective design optimisation of antennas
PublicationAbstract: Information regarding the best possible design trade-offs of an antenna structure can be obtained through multiobjective optimisation (MO). Unfortunately, MO is extremely challenging if full-wave electromagnetic (EM) simulation models are used for performance evaluation. Yet, for the majority of contemporary antennas, EM analysis is the only tool that ensures reliability. This study introduces a procedure for accelerated...
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Fluctuation enhanced gas sensing using UV irradiated Au-nanoparticle-decorated WO3-nanowire films
PublicationWO3 nanowires (WO3-NWs) decorated with gold nanoparticles (AuNPs) were utilized in resistive gas sensor devices to detect ethanol by use of fluctuation enhanced sensing (FES). The experimental system records both DC resistance and fluctuations of the sensing film. Our data verify that the sensitivity and selectivity of the gas sensor are improved by applying FES when the sensor is stimulated with a combination of UV light and heating....
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Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards
PublicationIn the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulation and evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modeling and solution rely on finite element methods and cover the simulation of the structure’s properties along with the influence of the marine environment – sea currents, wave and wind loading,...
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Fatigue Bending of V-Notched Cold-Sprayed FeCoCrNiMn Coatings
PublicationCold-spray coatings were produced by FeCoCrNiMn high-entropy alloy powders deposited on carbon steel substrate. The coatings were realized at intermediate temperature and high pressure (at 1100 °C and 7 MPa). The coating microstructure was characterized by scanning electron microscopy and X-ray diffraction, revealing a very dense deposition and high flattening ratio of the splatted particles. This had a large influence on the...
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Comparison of strain results at a laser weld notch obtained by numerical calculations and experimental measurements
PublicationIn the development of ship structures applying new materials and it’s purposeful placement play an important role. During the last years, especially in a construction of ro-ro type vessels, the usage of novel sandwich structures in cargo decks is profitable. Steel sandwich panel is an innovative solution which at a todays state of development can be used for the construction of any members not taking part in a global bending of...
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Energy efficiency of electric multiple units in suburban operation
PublicationThis thesis presents approach to analysis of energy efficiency of a suburban rail network, using novel models developed on the Matlab/Simulink basis. Necessary features and requirements for such models were determined thru in-depth review of the source literature in all applicable fields: electrified transportation systems, electric multiple units construction, vehicle drivetrains and finally, existing simulation methods. Existing...
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A new model of fuel spray shape at early stage of injection in a marine Diesel engine
PublicationIn the cylinders of a marine diesel engine, self-ignition occurs in very shortly time after the fuel injection into the combustion chamber. Therefore, the paper present was to develop a model of diesel fuel spray for the early stage of fuel spray for in marine diesel engine. There were taken into consideration the main aspects technical such as nozzle diameter of marine engine injector and backpressure in combustion chamber. In...
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Studies on Aminoanthraquinone-Modified Glassy Carbon Electrode: Synthesis and Electrochemical Performance toward Oxygen Reduction
PublicationIn this paper, 9,10-anthraquinone (AQ) derivative-modified glassy carbon (GC) electrodes were studied towards the electrochemical reduction of oxygen in aqueous and non-aqueous solutions. The reaction of 1-chloro-9,10-anthraquinone with aliphatic diamines was applied for the synthesis of amino-9,10-anthraquinone derivatives. The obtained AQ derivatives were grafted onto the surface of glassy carbon electrodes by electropolymerisation...
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Open-Phase Fault Detection Method for Sensorless Five-Phase Induction Motor Drives with an Inverter Output Filter
PublicationThe paper presents the sensorless five-phase induction motor drive implementation with an inverter output filter with third harmonic injection. For the sensorless operation, the required observers are presented for the first and third harmonics with consideration of the inverter output filter. Moreover, the interaction of the observers and the control system is capable to handle a deactivation of one or two phases, which improves...
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A Low-Cost System for Far-Field Non-Anechoic Measurements of Antenna Performance Figures
PublicationPrototype measurements are the key step in the development of antenna structures. Typically, their far-field characteristics are validated in expensive, dedicated facilities such as open range sites, or anechoic chambers. Despite being necessary for obtaining high-precision data (e.g., for device qualification), the use of costly infrastructure might not be fully justified when the main goal of measurements includes demonstration...
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Designing control strategies of aeration system in biological WWTP
PublicationThe paper presents the complete design processes of a novel aeration control systems in the SBR (Sequencing Batch Reactor) wastewater treatment plant (WWTP). Due to large energy expense and high influence on biological processes, the aeration system plays a key role in WWTP operation. The paper considers the aeration system for a biological WWTP located in the northeast of Poland. This system consists of blowers, the main collector...
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Tailoring optical constants of few-layer black phosphorus coatings: Spectroscopic ellipsometry approach supported by ab-initio simulation
Publication2D black phosphorus (BP) has attracted extensive attention as an anisotropic platform for novel optoelectronic and polarizing optics applications. Insight into the factors that tune the optical and polarizing properties of 2D BP reveals their essential influence on BP-based photonic and optoelectronic devices. In this work, studies of the optical constants of few-layer black phosphorus coatings are studied and discussed, with particular...
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Analiza wydajności kolektora słonecznego przeznaczonego dla systemu ogrzewania budynku o niskim zapotrzebowaniu na ciepło
PublicationNiniejsza praca przedstawia wyniki badań numerycznych kolektora słonecznego, przeznaczonego dla budynków o niskim zapotrzebowaniu na ciepło. W pracy przedstawiono nowatorską koncepcję kolektora słonecznego o obniżonej wydajności, niskich kosztach wykonania oraz wykorzystującego istniejące elementy konstrukcji przekryć budynku. Istotną zaletą kolektora jest brak ingerencji w architekturę zewnętrzną budynku. Za pomocą symulacji numerycznej...
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Simple Computational Methods in Predicting Limit Load of High-Strength Cold-Formed Sections due to Local Buckling: A Case Study
PublicationCold-formed thin-walled sections are prone to local buckling caused by residual stresses, geometrical imperfections and inconsistency of material properties. We present a real case of buckling failure and conduct a numerical and experimental study aimed to identify methods capable of predicting such failures. It is important because designers of structures are getting more FEA-oriented and tend to avoid lengthy procedures of cold-formed...
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ARRAY OF MINIJETS – THERMAL AND HYDRAULIC PHENOMENA IN BOUNDARY LAYER
PublicationPresented work considers flow and thermal phenomena occurring in the system consisting of minijets array and heated with constant heat flux surface. Numerical analyses, based on the mass, momentum and energy conservation laws, were conducted. Focus was placed on the proper model construction, in which turbulence and boundary layer modelling was crucial. Calculations were done for various mass flow rates. The main calculations were...
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Dynamic Nanoimpedance Characterization of the Atomic Force Microscope Tip-Surface Contact
PublicationNanoimpedance measurements, using the dynamic impedance spectroscopy technique, were carried out during loading and unloading force of a probe on three kinds of materials of different resistivity. These materials were: gold, boron-doped diamond, and AISI 304 stainless steel. Changes of impedance spectra versus applied force were registered and differences in the tip-to-sample contact character on each material were revealed. To...
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Konzetrationslöschung durch Energieübertragung bei der Lumineszenz von Lösungen
PublicationThe absorption spectra and quantum yields of the fluorescence of rhodamine 6 G are investigated in two different water-glycerol mixtures as a function of the rhodamine concentration. The observed concentration quenching is attributed to the formation of rhodamine dimers and the decrease in quantum yield is compared with theoretical concepts about concentration quenching by energy transfer to the dimers.
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Experimental and analytical analysis of punching shear in flat slabs supported on column topped with concrete head
PublicationAn experimental laboraatory test of the two series of slab-column elements topped with drop panels of varying sizes is described in this paper. The scope of the paper is to investigate the influence of the drop panel size and stiffness on the behaviour of the connection between the flat slab and the column topped by the concrete head. The impact of the head size and stiffness is analysed analytically and experimentally. The experimental...
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Rola i znaczenie zbiornika sieciowego w kształtowaniu hydrauliki i jakości wody w systemie wodociągowym
PublicationEksploatacja zbiornika sieciowego powinna zapewniać cykliczną wymianę wody w jego komorach. Koniecznym warunkiem prawidłowej eksploatacji zbiornika jest zgodność założeń projektowych ze stanem faktycznym. Praktyka eksploatacyjna wskazuje na szereg nieprawidłowości w tym względzie. Z powodu lokalizacji zbiornika sieciowego za nisko lub za wysoko albo wskutek błędów popełnionych w ustaleniu jego parametrów obserwuje się niestabilność...
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Mechatronic Design Towards Investigation of the Temporo-Mandibular Joint Behaviour
PublicationA significant problem of the temporo-mandibular joint (TMJ) research is lack of data concerning geometry and position of TMJ discs. It leads to necessity of developing a driving method of the process optimization, which is based on chosen techniques of mechatronic design. In particular, the latter concerns a technique of experimentally supported virtual prototyping. On this stage, the research is characterized by well-verified...
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Modified Inductive Multi-Coil Wireless Power Transfer Approach Based On Z-Source Network
PublicationThis article presents a non-conventional approach to a multi-coil wireless power transfer system based on a Z-source network. The novelty of the approach lies in the use of a Z-source as a voltage source for energy transmission through the wireless power transfer coils. The main advantage is in a reduced number of semiconductors. This paper provides the design approach, simulation and experimental study. Feasibility and possible...
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Towards truly sustainable IoT systems: the SUPERIOT project
PublicationThis paper provides an overview of the SUPERIOT project, an EU SNS JU (Smart Networks and Services Joint Undertaking) initiative focused on developing truly sustainable IoT systems. The SUPERIOT concept is based on a unique holistic approach to sustainability, proactively developing sustainable solutions considering the design, implementation, usage and disposal/reuse stages. The concept exploits radio and optical technologies...
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Born–Oppenheimer potential energy curves of NaK from the optimised atomic basis sets
PublicationThe article presents adiabatic potential energy curves of the ground and excited electronic states for the diatomic NaK molecule. The calculations were made using the ab initio computational methods to include electron correlation. The studied molecule was calculated as the effective two-electron problem, in which only the valence electrons of the molecule are explicitly taken into account. The remaining electrons with atomic nuclei...
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Generalized regression neural network and fitness dependent optimization: Application to energy harvesting of centralized TEG systems
PublicationThe 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,...
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Task Scheduling – Review of Algorithms and Analysis of Potential Use in a Biological Wastewater Treatment Plant
PublicationThe idea of task scheduling is to increase the efficiency of a system by minimising wasted time, evenly loading machines, or maximising the throughput of machines. Moreover, the use of appropriate scheduling algorithms often leads to a reduction in the energy costs of the process. Task scheduling problems are found in a variety of industrial areas, and their scale changes significantly depending on the problem. This review shows...
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Shaft friction from the DMT and direct shear interface tests
PublicationThe article presents preliminary attempt to create tri-linear transfer curves for describing pile behaviour under axial loading. Transfer curves would use the parameter measured in dilatometer test, particularly a constrained modulus MDMT. The proposed method is based on concrete rough and smooth interface tests performed in a direct shear apparatus. Based on the obtained mobilization curves, relationships were created between...
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Diagnostic Model of Crankshaft Seals
PublicationT he paper presents a research stand being a diagnostic model of radial lip seals used, among others, on crankshafts of piston combustion engines in order to identify the correctness of their operation. The possibility of determining the technical condition of lip seals on the basis of the proposed coefficient of correctness of operation has been described. T he basic features of seals influencing their correctness of...
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Influence of Additional Loads on Chosen Gait Parameters and Muscles Activity
PublicationThis paper is devoted to human motion analysis and comparison of chosen kinematics parameters during normal gait with and without additional load in a form of backpack. A stability in both cases were compared in both frontal and sagittal planes, by applying a video tracking system. Experimental tests performed on treadmill, passive markers, placed on volunteers bare skin were used. Additionally, an infra-red camera was employed...