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Search results for: life cycle cost
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Aquaponics Based Artificial Biosphere Included in Architecture: From Mitigation of Negative Impacts to Positive Added Values of Urban Spatial Structures on Local, Regional and Global Scale
PublicationTechnologies may appear faster than spatial planning can afford it. Alt hough applying new technologies solve particular problems, it may also create new ones. Many negative consequences of implementing new technologies are visible a fter years or decades – they accumulate until the need of solving them. According to The Hannover Principles (McDonough & Braungart 2013) one should, by example not think about...
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Organic solvents aggregating and shaping structural folding of protein, a case study of the protease enzyme
PublicationLow solubility of reactants or products in aqueous solutions can result in the enzymatic catalytic reactions that can occur in non-aqueous solutions. In current study we investigated aqueous solutions containing different organic solvents / deep eutectic solvents (DESs) that can influence the protease enzyme's activity, structural, and thermal stabilities. Retroviral aspartic protease enzyme is responsible for the cleavage of the...
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COMPREHENSIVE MODELLING OF THE COST EFFECTIVNESS OF RAILWAY LINE ELECTRIFICATION
PublicationSubject of this paper is the mathematical model estimating the Economical threshold between usage of combustion engine traction and electrical traction for new and modernized railway passenger communication lines. Currently available models do not coincide with the whole complexity of the problem. The proposed model was implemented into Matlab and then validated on “Pomorska Kolej Metropolitalna” investment time-frame and its cost...
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SimLE Stardust: How an experiment evolved from student tinkering to a stratospheric research platform
PublicationStratospheric balloons are one of the most accessible methods of near space exploration. Their applications include capturing of extreme living organisms whose existence in the stratosphere has been suggested in the literature. These potential microorganisms would have evolved to survive the unique environment of low temperature, low pressure and high solar radiation. This makes the development of...
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Derivation of motor mean phase currents in PMSM drives operating with low switching-to-fundamental frequency ratio
PublicationPulse width modulation (PWM) of inverter output voltage causes the waveforms of motor phase cur-rents to consist of distinctive ripples. In order to provide suitable feedback for the motor current con-trollers, the mean value must be extracted from the currents’ waveforms in every PWM cycle. A com-mon solution to derive the mean phase currents is to sample their value at the midpoint of a symmetrical PWM cycle. Using an assumption...
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Molecular mechanism and energetics of coupling between substrate binding and product release in the F 1 -ATPase catalytic cycle
PublicationF1-ATPase is a motor protein that couples the rotation of its rotary γ subunit with ATP synthesis or hydrolysis. Single-molecule experiments indicate that nucleotide binding and release events occur almost simultaneously during the synthesis cycle, allowing the energy gain due to spontaneous binding of ADP to one catalytic β subunit to be directly harnessed for driving the release of ATP from another rather than being dissipated...
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Carbon dioxide sequestration by industrial wastes through mineral carbonation: Current status and perspectives
PublicationMineral carbonation using natural minerals or industrial wastes is a safe and promising strategy for CO2 sequestration. Application of industrial wastes for this purpose has significant ecological and environmental value, which is one of the key green technologies in the global carbon mitigation. This review summarizes the current research status of CO2 mineralization by industrial wastes. This work surveys the mechanisms and capacities...
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Exergy analysis of a negative CO2 emission gas power plant based on water oxy-combustion of syngas from sewage sludge gasification and CCS
PublicationA power cycle with water-injected oxy-combustion (water cycle) is investigated by exergy analysis. It is fueled with syngas (aka. producer gas) from gasification of sewage sludge. The cycle is equipped with a spray-ejector condenser (SEC). CO2 is separated and compressed for transportation and storage. The net delivered electric power is 31% of the fuel exergy. The task efficiency is 39% when the flue gas bleed to gasification...
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Feasibility of combined diesel engine - steam turbine in power station operating in the maritime
PublicationCompression-ignition engines used in ship technology as main propulsion engines are large units reaching even to 50-60 MW. Currently, the efficiency of such engines amounts to 45-50%. With such a large power unit, exhaust gases leaving the engine contain very large quantities of heat available for further treatment. Exhaust gases from the piston engine contain about 25% of the heat supplied to the engine in the fuel. Using the...
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Design analysis of combined gas-vapour micro power plant with 30 kW air turbine
PublicationThe article presents basic results of the design analysis of a combined gas-vapour micro power plant with a waste-heat boiler without exhaust reheat, working in the vapour section in the Organic Rankine Cycle (ORC) system. The analysis concerned working media most frequently used in those types of power plants and planned to be used in future. The object of the analysis was a micro power plant with a 30 kW gas (air) turbine for...
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Design analysis of combined gas-vapour micro power plant with 30 kW air turbine
PublicationThe article presents basic results of the design analysis of a combined gas-vapour micro power plant with a waste-heat boiler without exhaust reheat, working in the vapour section in the Organic Rankine Cycle (ORC) system. The analysis concerned working media most frequently used in those types of power plants and planned to be used in future. The object of the analysis was a micro power plant with a 30 kW gas (air) turbine for...
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Analysing selection of low-temperature medium for cogeneration micro power plant
PublicationThe article analyses the ORC system working with dry and wet low-boiling media which are most frequently used in installations of this type. Two types of cycles were examined, which were the cycle with heat regeneration for dry media: fc72, hfe7100, R227ea, R245fa, R423a and R600a, and the cycle without heat regeneration for wet media: R11, R12, R134a, R718 and 507a. The calculations were performed for the assumed required thermal...
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Analysing selection of low-temperature medium for cogeneration micro power plant
PublicationThe article analyses the ORC system working with dry and wet low-boiling media which are most frequently used in installations of this type. Two types of cycles were examined, which were the cycle with heat regeneration for dry media: fc72, hfe7100, R227ea, R245fa, R423a and R600a, and the cycle without heat regeneration for wet media: R11, R12, R134a, R718 and 507a. The calculations were performed for the assumed required thermal...
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WSPÓŁPRACA BLOKU GAZOWO-PAROWEGO Z OBIEGIEM ORC = Combinded power plant in cooperation with ORC
PublicationIn the paper presented is the idea of a combined gas and steam power plant cooperation with a low temperature organic Rankine cycle ORC unit. Considerations presented in the paper are accomplished for the Gorzów CHP. The intention of present analysis is heat recovery of low temperature energy and its further use in ORC cycle in order to produce electricity, without increase in fuel consumption. Waste energy is recovered from the...
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Endometrial nitric oxide production and nitric oxide synthases in the equine endometrium: Relationship with microvascular density during the estrus cycle
PublicationNitric oxide (NO) plays an important role in angiogenesis and in the regulation of the blood flow. This study was carried out to investigate (i) the effects of endogenous estrogens and progestins and exogenous progesterone (P(4)) (5 ng/ml or 1 microg/ml) or estradiol 17beta (E(2)beta) (50 pg/ml or 1 microg/ml) on in vitro endometrial NO synthesis; (ii) the presence of different isoforms of NO synthase;...
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Development of a spray-ejector condenser for the use in a negative CO2 emission gas power plant
PublicationOne promising solution for developing low-emission power technologies is using gaseous fuel combustion in pure oxygen when the exhaust gas mixture is composed of H2O and CO2, and where CO2 is separated after steam condensation. The paper presents the results of computational analyses providing to the Spray-Ejector Condenser (SEC) development, which is one of the crucial components of the negative CO2 gas power plant (nCO2PP) cycle...
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Thermodynamic and economic analysis of nuclear power unit operating in partial cogeneration mode to produce electricity and district heat
PublicationThis paper presents the methodology of techno-economic analysis for a nuclear unit operating in partial cogeneration mode and its application for the case study: a nuclear power plant planned in Poland. The research objectives were: to propose EPR, AP1000 and ESBWR nuclear condensing-extraction turbine systems modifications required for operation in cogeneration, to determine optimal heat production and heat transport line (HTL)...
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Technical and economic conditions of supplying residential consumers with heat from nuclear power plant
PublicationThe reduction of CO2 emission requires technological shift towards carbon-free options. Cogeneration of electricity and heat based on coal and natural gas will experience generation cost increase, if the costs of emissions are imposed on the plant operators. Therefore, nuclear and renewable options should be considered. In this paper, we present the concept of electricity and heat supply system with nuclear condensing turbine adapted...
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KOMPOZYTOWY MOST PIESZO - ROWEROWY
PublicationPaper presents the composite foot and cycle bridge developed in FOBRIDGE grant cofinanced by The National Centre for Research and Development and realized by consortium of Gdansk University of Technology (leader), Military University of Technology in Warsaw and ROMA Sp. z o.o. in Toruń. The purpose of the grant was to design a shell type single span foot and cycle bridge made of composite materials, with the assumption of manufacturing...
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Reduction of CO2 Emissions from Offshore Combined Cycle Diesel Engine-Steam Turbine Power Plant Powered by Alternative Fuels
PublicationDiverse forms of environmental pollution arise with the introduction of materials or energy that exert adverse effects on human health, climate patterns, ecosystems, and beyond. Rigorous emission regulations for gases resulting from fuel combustion are being enforced by the European Union and the International Maritime Organization (IMO), directed at maritime sectors to mitigate emissions of SOx, NOx, and CO2. The IMO envisions...
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Design Analysis of Micro Gas Turbines in Closed Cycles
PublicationThe problems faced by designers of micro-turbines are connected with a very small volume flow rate of working media which leads to small blades’ height and high rotor speed. In the case of gas turbines this limitation can be overcome by the application of a closed cycle with very low pressure at the compressor inlet (lower than atmospheric pressure). In this way we may apply a micro gas turbine unit of accepted efficiency to work...
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A stochastic approach for the solution of single and multi – objective optimisation problems of biological processes in sequencing batch reactor
PublicationThis paper investigates the impact of implementing single and multi-optimisation solutions on the biological treatment process in a sequencing batch reactor (SBR). The research is based on a case study of the water resource recovery facility (WRRF) in Swarzewo, Northern Poland. The paper introduces the adaptive extremum seeking control (ESC) method for dissolved oxygen (DO) concentration control and places it in a layered control structure....
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Ranking of Heterogeneous Catalysts Metals by Their Greenness
PublicationCatalysis is very important process in industry and laboratory practice, especially from the point of green chemistry principles. However, eco-friendly character of heterogeneous catalysts, containing transition metal components has not been evaluated, yet. Therefore, we perform a comprehensive assessment of 18 heterogeneous metal catalysts (Pd, Pt, V, Co, Ni, Mo, Ru, Mn, Au, Cu, Cd, Zr, Fe, Rh, Ir, Sn, Zn, Ag) using multicriteria...
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Enhanced Charge Storage Mechanism And Long-Term Cycling Stability In Diamondized Titania Nanocomposite Supercapacitors Operating In Aqueous Electrolytes
PublicationThe long cycle life stability jointly with high energy density are limiting broader feasible applications of supercapacitors. The novel diamondized titania nanocomposite supercapacitors deliver high power and energy densities along with high capacitance retention rates. Supercapacitor electrodes were fabricated utilizing a combination of Ti anodization followed by chemical vapor deposition resulting in simultaneous growth of complex...
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Problemy zarządzania bezpieczeństwem obiektu przemysłowego podwyższonego ryzyka
PublicationW rozdziale przedstawiono wybrane zagadnienia dotyczące zarządzania bezpieczeństwem w zautomatyzowanym złożonym obiekcie podwyższonego ryzyka. Pokazano, że ryzyko strat można istotnie ograniczyć stosując odpowiednie rozwiązania techniczne w postaci warstwowego systemu zabezpieczeń, który obejmuje podstawowy system sterowania procesem, człowieka-operatora i system automatyki zabezpieczeniowej. Podkreślono znaczenie właściwego zaprojektowania...
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Multi-Criteria Approach in Multifunctional Building Design Process
PublicationThe paper presents new approach in multifunctional building design process. Publication defines problems related to the design of complex multifunctional buildings. Currently, contemporary urban areas are characterized by very intensive use of space. Today, buildings are being built bigger and contain more diverse functions to meet the needs of a large number of users in one capacity. The trends show the need for recognition of...
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Impact of Cyclist Facility Availability at Work on the Number of Bike Commuters
PublicationThe article describes the results of research designed to establish whether cycle provision can influence the number of employees commuting by bike. To that end, employee surveys were conducted in three IT companies in 2012 and 2016. The questionnaire asked about travel behaviour and what the staff thought about their company’s provision of cyclist facilities. Since 2012 each of the companies has moved its head office and the...
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Comprehensive thermodynamic analysis of steam storage in a steam cycle in a different regime of work: A zero-dimensional and three-dimensional approach
PublicationDue to the current trends aiming to reduce carbon dioxide emissions by increasing the use of renewable energy sources, changes are required in the operation of coal-fired steam units. The unstable nature of renewable energy sources, depending on weather conditions, means that the amount of energy produced varies and is not always in line with peak demand. To ensure the security and stability of energy supplies in the energy system,...
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Enhancing nitrogen removal in the partial denitrification/anammox processes for SO4− - Rich wastewater treatment: Insights into autotrophic and mixotrophic strategies
PublicationThe investigation of partial denitrification/anammox (PD/anammox) processes was conducted under autotrophic (N–S cycle) and mixotrophic (N–S–C cycle) conditions over 180 days. Key findings revealed the remarkable capability of SO42--dependent systems to produce NO2− effectively, supporting anaerobic NH4+ oxidation. Additionally, SO42− served as an additional electron acceptor in sulfate reduction ammonium oxidation (SRAO). Increasing...
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HIERARCHICAL CYCLES IN MODERN POWER SYSTEMS – EXERGY ANALYSIS UNDER PART LOADS
PublicationThe aim of the paper is to investigate thermodynamic efficiency of advanced hierarchic power cyclesunder partial loads by using of exergy analyze. Advanced hierarchical power systems arecomposed of few energy conversion cycles, most common are steam and gas cycles in various configurations, but they may contain fuel cells, ORC, lithium bromide absorption chillers and others. Moreover hierarchical cycles can be powered by several...
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Pozwolić odejść, czyli... Granice interwencji
PublicationCelem tekstu jest zwrócenie uwagi na problem ostatecznej granicy interwencji konserwatorskich wobec zabytków architektury w kontekście holistycznej koncepcji ochrony dziedzictwa. Tekst adresowany jest do polskich czytelników ze względu na szczególne odniesienia do sytuacji polskiego systemu ochrony dziedzictwa. Choć architektura należy do sfery sztuk użytkowych, większość budynków nie powstawała...
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Power augmentation of PGE Gorzow's gas turbine by steam injection - thermodynamic overview
PublicationThe impact of steam injection upon a gas turbine and a combined power plant performance has been investigated. This article describes and summarizes possibilities of modification for current gas turbine in PGE Gorzow power plant into the Cheng cycle. Our modification deals with a thermal cycle, in which steam produced in a heat recovery steam generator is injected into the gas turbine's combustion chamber. It has been proved that...
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Consumerism and the Quality of Life
PublicationHigh level of consumption, driven by marketing activities, the pleasure and joy of possession and the accumulation of material goods are often associated with prosperity, sense of happiness and fulfilment in life. On a broader scale, economic indicators related to production and consumption are used to define the well-being and quality of life in societies. Unfortunately, the phenomenon of consumerism entails negative social and...
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Hat problem on odd cycles
PublicationThe topic is the hat problem in which each of n players is randomly 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 a win. In this version every player can...
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A Direct Modulation for Matrix Converters based on the Onecycle Atomic operation developed in Verilog HDL.
PublicationThis paper presents a fast direct Pulse Width Modulation (PWM) algorithm for the Conventional Matrix Converters (CMC) developed in Verilog Hardware Description language (HDL). All PWM duty cycle calculations are performed in one cycle by an atomic operation designed as a digital module using FPGA basic blocks. The algorithm can be extended to any number of output phase. The improved version of the discontinuous Direct Analytic...
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STUDY ON THE EFFECTIVENESS OF THE TURBINE CONDENSER AIR EXTRACTION SYSTEM USING HYDRO EJECTORS
PublicationThe aim of the paper is to investigate the effectiveness of the 18K380 steam turbine condenser air extraction system using hydro ejectors. Motivation for the analysis is a need of improvement of the energy conversion ratio of the power plant. To achieve this goal it is necessary to establish efficiency of each subsystem of the energy cycle. The air extraction system is not a highly power consuming system but it has great impact...
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Recent progress in research on the cutting processes of wood. A review COST Action E35 2004-2008: Wood machining - micromechanics and fracture
PublicationZaprezentowano postępy w badaniach przecinania drewna ze szczególnym uwzględnieniem nowych metod dedykowanych zwiększeniu wydajności materiałowej w tartacznictwie. Zademonstrowano przydatność współczesnej mechaniki pękania do szacowania mocy skrawania dla pił, których wartości rozwarcia są różne od pił użytych w badaniach skrawalnościowych. W tych ostatnich wyznaczano wiązkość materiału obrabianego oraz naprężenia tnące. Badania...
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Recent progress in research on the cutting processes of wood. A review COST Action E35 2004-2008: Wood machining - micromechanics and fracture
PublicationZaprezentowano postępy w badaniach przecinania drewna ze szczególnym uwzględnieniem nowych metod dedykowanych zwiększeniu wydajności materiałowej w tartacznictwie. Zademonstrowano przydatność współczesnej mechaniki pękania do szacowania mocy skrawania dla pił, których wartości rozwarcia są różne od pił użytych w badaniach skrawalnościowych. W tych ostatnich wyznaczano wiązkość materiału obrabianego oraz naprężenia tnące. Badania...
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Possibilities of Increasing the Overall Efficiency of Gas-steam CHP Microplant
PublicationThe paper presents ways to increase the efficiency of a gas-steam micro power plant by modifying the cycle combination. The modification consists in partial release of the fluid downstream of the gas turbine and using it for ORC fluid overheating and evaporation. Advantages of this solution over the simplest gas and steam cycles’ combination are demonstrated.
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The Environmental Benefits of Photovoltaic Systems: The Impact on the Environment in the Production of Photovoltaic Systems: With a Focus on Metal Recovery
PublicationGreenhouse gases (GHGs) such as carbon dioxide, nitrous oxide and methane, trap heat and energy, thus preventing solar radiation from escaping back into space. As the quantity of greenhouse gases in the atmosphere increases so does the trapped heat and corresponding global temperature. As a result, storms become more violent, droughts more prevalent, glaciers melt, and sea levels rise, to name but a few effects of a rapidly changing...
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ENVIRONMENTAL ASSESSMENT OF SOLAR CELL MATERIALS
PublicationIn today’s world, fossil fuels, including coal, oil, and gas, are the primary energy sources from which electricity is obtained. As they are exhaustible and their exploitation has a negative impact on the natural environment, they should be, at least partially, replaced by renewable energy sources. One of these sources is solar energy. The use of solar energy releases no CO2, SO2, or NO2 gases, and does not contribute to global...
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Storm petrels as indicators of pelagic seabird exposure to chemical elements in the Antarctic marine ecosystem
PublicationData on trace element bioavailability in the south-polar marine ecosystem is still scarce, compared to that relating to temperate zones. Seabirds can be used as indicators of ecosystem health and sentinels of environmental pollution, constituting a link between marine and terrestrial environments. Here, we analysed the concentration of 17 elements (with special emphasis on mercury, Hg) in feathers of adults and chicks of two pelagic...
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Highly Conserved Homotrimer Cavity Formed by the SARS-CoV-2 Spike Glycoprotein: A Novel Binding Site
PublicationAn important stage in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) life cycle is the binding of the spike (S) protein to the angiotensin converting enzyme-2 (ACE2) host cell receptor. Therefore, to explore conserved features in spike protein dynamics and to identify potentially novel regions for drugging, we measured spike protein variability derived from 791 viral genomes and studied its properties by molecular...
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Thermodynamic Analysis of Negative CO2 Emission Power Plant Using Aspen Plus, Aspen Hysys, and Ebsilon Software
PublicationAbstract: The article presents results of thermodynamic analysis using a zero-dimensional mathematical models of a negative CO2 emission power plant. The developed cycle of a negative CO2 emission power plant allows the production of electricity using gasified sewage sludge as a main fuel. The negative emission can be achieved by the use this type of fuel which is already a “zeroemissive” energy source. Together with carbon capture...
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A new duty cycles calculation method in pulse width modulation for direct matrix converters based on the shape function concept
PublicationPaper presents a new approach to duty cycle calculation in pulse width modulation for direct matrix converters. The essence of the proposed method is the use of elementary shape function of finite element. The algorithm for calculating the duty cycles was reduced to simple operations on the coordinates of input and output voltage vectors without trigonometric functions.
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The basics of design and experimental tests of the commutation unit of a hydraulic satellite motor
Publicationhe article presents an analytical method to design the commutation unit in a hydraulic satellite motor. It is shown that the size of the holes feeding the working chambers and their location on the plates closing those chambers depends on the geometrical dimensions of the working mechanism. The overlap in the commutation unit depends on the rotational speed range. It is demonstrated that the geometrical dimensions of the commutation...
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Influence of water and mineral oil on the leaks in satellite motor commutation unit clearances
PublicationThe article describes the flow rates of mineral oil and water flowing, as working media, through the commutation unit of a hydraulic satellite motor. It is demonstrated that geometrical dimensions of commutation unit clearances change as a function of the machine shaft rotation angle. Methods for measuring the rate of this flow and the pressure in the working chamber are presented. The results of pressure measurements in the working...
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On the use of a charge balancing method for low energy measurements
PublicationThe paper presents the method for the estimation of the energy consumption of the low-power microcontroller-based devices. Due to high dynamics of the changes of the supply current of the tested devices during the operational cycle, the consumed energy estimation is not easy. In order to avoid disadvantages of known methods, the charge balancing method was employed similarly like in some types of A/D converters.
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Developing a cycling subsystem as part of a sustainable mobility strategy: the case of Gdansk
PublicationModal share is an important component in developing sustainable transport within a city. In recent years, many cities have set modal share targets for balanced and sustainable transport modes: 30% of public transport and 30% of non-motorized (cycling and walking) modes. Gdansk strategic documents have set similar goals with some actions already taken towards those goals. The cycle network is increasing popular. Gdansk’s cycling...
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Porous carbon derived from rice husks as sustainable bioresources: insights into the role of micro-/mesoporous hierarchy in hosting active species for lithium–sulphur batteries
PublicationThe exploration of natural resources as sustainable precursors affords a family of green materials. Exploring highly abundant and available biowaste precursors remaining from food processing throughout a scalable and cost-effective material synthesis path is highly important especially for new materials discovery in emerging energy storage technologies such as lithium–sulphur (Li–S) batteries. Herein, we have produced a series...