Wyniki wyszukiwania dla: power supply
-
A NOVEL CONCEPT OF H2/O2 STEAM GENERATOR
PublikacjaThis paper presents an idea of hydrogen utilization to steam generation to drive a turbine and produce electricity or to supply a condenser as an element of heating system. Electrolysis process is considered as a source of hydrogen as well as oxygen. Hydrogen combustion with a stoichiometric ratio of pure oxygen produces steam at very high temperature. Steam temperature can be controlled by mixing the generated steam with liquid...
-
Displacement control in PWK-type pumps
PublikacjaThe most important, strategic goal however is creation of the variable displacement version of the new pump PWK. Thanks to full discharge of it's commutation mechanism from hydrostatic forces the variable pump can be directly controlled by low-energy actuator like proportional electromagnet or stepping motor. It means that costly and complicated hydraulic servomechanism (applied in all present variable displacement pumps) is no...
-
A method of earth fault loop impedance measurement without unwanted tripping of RCDs
PublikacjaIn low-voltage networks, earth fault loop impedance (EFLI) measurement is the basis for assessing the effectiveness of automatic disconnection of supply. Such a measurement is performed during initial and periodical verification, especially in a TN low-voltage network. Nowadays, due to widespread application of residual current devices (RCDs), such test is difficult in many circuits because RCDs operate during the test. In this...
-
Influence of the low ambient temperature on the start-up process of hydraulic pumps
PublikacjaStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with...
-
Dynamics of algae growth and nutrients in experimental enclosures culturing bighead carp and common carp: Phosphorus dynamics
PublikacjaThis is the third paper of the series about “Dynamics of algae growth and nutrients in experimental enclosures culturing bighead carp and common carp”. In this paper, phosphorus dynamics were investigated under the condition of culturing bighead carp and common carp with added fish food (nitrogen dynamics is discussed in the second paper because their behaviors are so different from each other). Nearly fifty days’ observation results...
-
A Framework for Enhancing Supplier Selection Process by Using SOEKS and Decisional DNA
PublikacjaAbstract. Supplier selection process is one of the significant stages in supply chain management for industrial manufactured products. It plays an integral role in the success of any manufacturing organization and is an important part starting right from selecting raw material to dispatch of finished products. This paper contributes to enhance the supplier selection process by proposing a multi-criteria decision making framework...
-
Control design for slow speed positioning
PublikacjaThe problem under study is a synthesis of position and heading control system for low frequency model of surface vessel described by 3 DOF mathematical model. The recursive vectorial backstepping control design was used to keep fixed position and heading in presence of wave disturbances. The controller has been simulated on computer model of scaled supply vessel. It has been assumed that the actuators produce generalized forces...
-
Energy policy and the role of bioenergy in Poland
PublikacjaPrzedstawiono sytuacje energetyczną kraju. Omówiono poszczególne sektory wytwarzania energii oraz zapotrzebowania na energię i paliwa. Omówiono przekształcenia sektorów energetycznych w Polsce na przestrzeni lat 1990-2002. Na tym tle przedstawiono techniczne, ekonomiczne, społeczne i prawne aspekty rozwoju energetyki źródeł odnawialnych a w szczególności opartych o bioenergię. Przedstawiono wnioski dla Polski płynące z dotychczasowych...
-
Sensorless induction motor drive with voltage inverter and sine-wave filter
PublikacjaThis paper presents a speed sensorless control system of an induction motor with an output LC filter. It is known that the parameters design of the filter gives sine wave motor supply voltage but complicates control and estimation process. The reason is that the voltage drop and phase shift between filter input and output signals are imposed, and hence the motor voltages and currents differ from the inverter output waveforms. To...
-
SERVICE ORIENTED SCENARIOS FOR SUPPORT ENTERPRISE PROJECT MANAGEMENT
PublikacjaIn the paper, a service oriented architecture is used to describe various scenarios of human-oriented enterprises. They can be modeled by BPMN to show basic information flow. We consider business scenarios to present another modeling solution called service orchestration or service mashup. That approach gives an opportunity for the right management through taking the best possible choice of services, or composition of services....
-
Water-lubricated stern tube bearing - experimental and theoretical investigations of thermal effects
PublikacjaThe paper presents research results of thermal phenomena accompanying operation of a water-lubricated stern tube bearing with axial grooves. Experimental tests revealed, that intensity of forced axial flow has strong influence on bush temperature. Numerical simulations focused on investigation of the thermal phenomena under operation of water-lubricated journal bearing showed, that restricted axial flow promotes backflow of the...
-
Experimental research on a hydrodynamic thrust bearing with hydrostatic lift pockets: Influence of lubrication modes on bearing performance
PublikacjaThe aim of the study is to investigate the performance of a thrust bearing equipped with hydrostatic lift pockets under different lubrication modes. Three types of flat land bearing lubrication modes are studied experimentally: hydrostatic lubrication (HS; forced oil injection to the pockets), hybrid lubrication (HS + HD; hydrostatic lubrication combined with the external forced bearing oil supply) and hydrodynamic lubrication...
-
Revitalisation Living Lab as a Format to Accelerate an Energy Transition in Polish Rural Areas: The Case Studies of Metropolitan Outskirts Gdańsk-Orunia and Lubań
PublikacjaThe paper deals with the issue of energy transition in the revitalization process dedicated to the rural and semi-rural areas of the Pomerania Region (PR). Two distinct areas, located in sub- and ex-urban zones of the Gdańsk-Gdynia-Sopot Metropolitan Area (OMGGS), in which bottom-up community initiatives have been playing a key role in the transformation, have been focused on. The village of Lubań (Municipality of Nowa Karczma)...
-
Logistics of Transnational Corporations as the Basis of Cooperation Between Ukraine and EU (for Poland Example)
PublikacjaThe article describes the scientific and theoretical basis for the organization of logistics management of modern international corporations, owning by assets in mining and metallurgical business in Ukraine and Poland; it had been analyzed the influence of transfer pricing mechanism as one of the main factors affecting on the efficiency of the organization of supply chain of resources (Ukrainian semi-finished goods) to ensure uninterrupted...
-
Study of Noise Propagation for Small Vessels
PublikacjaThe paper presents the results of the noise propagation analysis in ship structures tested in a number of AHTS (Anchor Handling Tug Supply) vessels. Statistical Energy Analysis (SEA) based on numerical model developed specially for the purpose of this numerical investigation were conducted. This numerical model enabled the analysis of both the structural elements and the acoustic spaces. For the detailed studies 47 points fixed...
-
Effect of Thermal Shock During Legionella Bacteria Removal on the Corrosion Properties of Zinc-Coated Steel Pipes
PublikacjaThe purpose of this investigation was to conduct the failure analysis of a water-supply system made from zinc-coated steel. The observed corrosion process had an intense and complex character. The brownish deposits and perforations were present after 2-3 years of exploitation. The electrochemical study based on the Tafel polarization, corrosion potential monitoring, and electrochemical impedance spectroscopy together with microscopic...
-
Shared multi-processor scheduling
PublikacjaWe study shared multi-processor scheduling problem where each job can be executed on its private processor and simultaneously on one of many processors shared by all jobs in order to reduce the job’s completion time due to processing time overlap. The total weighted overlap of all jobs is to be maximized. The problem models subcontracting scheduling in supply chains and divisible load scheduling in computing. We show that synchronized...
-
ASSESSMENT of PERFORMANCE of UMV (2024)
Kursy Online(W) Assessment of Performance of Unmanned Maritime Vehicles (W-Lecture) - DAPE - WIMiO AP-of-UMV (W) -DAPE - WIMiO The course entitled "Assessment of Performance of Unmanned Maritime Vehicles (W-Lecture)" is conducted for the DAPE WIMiO Students. The AP-of-UMV (W) course is to discuss the following problems: - major areas of application of UMV unmanned maritime vehicles, - sea environment, - types of UMV vehicles, -...
-
MARKETING STRATEGY - SPACE AS A PRODUCT.ARCHITECTURE AS A MARKETING DEVICE.
PublikacjaSpace has its measurable financial value. From the economic point of view place can be treated as a product that fights for appearing in tourists' and investors' consciousnesses. Space - treated as the object of demand and supply - becomes an element in a marketing game. To reach its maximal value the given space should be competitive to other spaces, from which it wants to stand out. However, in the field of architecture - and...
-
THE METHOD OF ENERGY-EFFICIENCY INVESTIGATIONS OF THE NEWLY PRODUCED MARINE FUELS THROUGH AN APPLICATION OF THE LABORATORY DIESEL ENGINE
PublikacjaThe article deals with one of the scientific issue solved within frames of the research project financed by Voivodeship Fund for Environmental Protection and Water Management in Gdansk, namely, in particular, the method of energy investigations of the self-ignition engine in conditions of its supply with a non-standard (modified) marine fuel. The representative results of engine tests worked out on the especially built laboratory...
-
Dynamic characteristics of the proton exchange membrane fuel cell module
PublikacjaThe paper describes a fuel cell based system and its performance. The system is based on two fuel cell units, DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and a set of measurement instruments. In the study presented in the paper a dynamic response of the proton exchange membrane (PEM) fuel cell system to unit step change load as well as to periodical load changing cycles...
-
Modeling of performance of a AUV vehicle towards limiting the hydro-acoustic field.
PublikacjaSome results of research devoted to the modeling of a AUV-Stealth vehicle performance towards limiting its hydro-acoustic field are presented in the paper. At the beginning the AUV-Stealth autonomous underwater vehicle concept is described. Then the method of research is introduced. Next the key design drivers of the AUV-Stealth vehicle are presented. Between them are the AUV-Stealth hull form, arrangement of internal spaces,...
-
Electrolytic corrosion of water pipeline system in the remote distance from stray currents– case study
PublikacjaCase study of corrosion failure of urban water supply system caused by the harmful effects of stray currents was presented. The failure occurred at a site distant from the sources of these currents namely the tramway and railway traction systems. Diagnosis revealed the stray currents flow to pipeline over a remote distance of 800 ÷ 1,000 meters from the point of failure. At the point of failure stray currents flowed from the pipeline...
-
Urban Freight Transport Demand Modelling and Data Availability Constraints
PublikacjaThe paper provides a review of urban freight transport demand modelling approaches confronted with constrains regarding adequate data provision from a perspective of the local authorities. Demand estimation models has been selected as a reference because they are the most representative in terms of inclusion of urban freight indicators which can be transformed into a decision-support tool for evaluation of freight measures. The...
-
PROBLEMS OF THE STARTING AND OPERATING OF HYDRAULIC COMPONENTS AND SYSTEMS IN LOW AMBIENT TEMPERATURE (PART V) METHODS ENSURING CORRECT START-UP OF HYDRAULIC COMPONENTS OF SHIP’S ONBOARD DEVICES IN LOW AMBIENT TEMPERATURES
PublikacjaA large number of hydraulic devices and systems are started in low ambient temperatures. A good example of such a device is the hoisting winch on the ship. Starting hydraulic drive units in thermal shock conditions (rapid supply of hot oil to the cold unit) may lead to incorrect operation of the actuating system, for instance, due to the loss of clearance between cooperating elements. The article presents methods to prevent the...
-
Evaluation of the influence of the opening pressure of a marine Diesel engine injector on the results of numerical simulation of the working cycle and their comparison with the results of the laboratory experiment
PublikacjaThe article presents the results of a numerical simulation of the working process carried out in a diesel engine. In the applied utility program DIESEL-RK, the laboratory engine Farymann Diesel type D10 was implemented. A selected inoperability of its functional fuel supply system - reduced opening pressure of the injector pinj - was introduced. The values of adequate diagnostic parameters were determined: working gas temperature...
-
Challenges associated with development of AUV - unmanned autonomous underwater vehicles to be operated using the AI-based control systems
PublikacjaThe last decade has been devoted towards further development of the UUV unmanned underwater vehicles which may be of two types. There are the USV unmanned surface vehicles and UUV unmanned underwater vehicles. There is a growing interest to work out and implement the fully advanced AUV autonomous underwater vehicles. The main drivers towards development of such the vehicles are the technologies of autonomous systems, sensors and...
-
The microbial community, its biochemical potential, and the antimicrobial resistance of Enterococcus spp. in Arctic lakes under natural and anthropogenic impact (West Spitsbergen)
PublikacjaThe sustainable management of small human communities in the Arctic is challenging. In this study, both a water supply system (Lake 1) under the natural impact of a bird-nesting area, and a wastewater receiver (Lake 2) were analysed in the vicinity of the Polish Polar Station on West Spitsbergen. Microbial community composition, abundance and activity were assessed in samples of the treated wastewater, lake water and sediments...
-
Chemical treatment of crystalline silicon solar cells as a main stage of pv modules recycling = Obróbka chemiczna krzemowych ogniw słonecznych jako najważniejszy etap w recyklingu modułów fotowoltaicznych
PublikacjaIn recent years, photovoltaic systems have gained worldwide recognition and popularity as a environmentally friendly way of solving energetic problems. However, a problem of utilizing worn out photovoltaic systems, amount of which will rapidly increase in the future, is yet to be solved. Establishing a technology of recycling and reusing obsolete photovoltaic panels is a necessity.Photovoltaic modules in crystalline silicon solar...
-
The enantiomeric determination of chloro-precursors of methamphetamine
PublikacjaImpurity profiling and classification of seized methamphetamine may supply valuable information with respect to the conditions and the chemicals used in the illicit methamphetamine manufacture and may provide information on the original source of the sample. Determination of the stereochemical makeup of forensic samples is important as well for the same reasons. Laboratories in many places are engaged in clandestine manufacture...
-
An Intergrated Model of Motion, Steering, Positioning and Stabilization of an Unmanned Autonomous Maritime Vehicle
PublikacjaIn 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....
-
Quantifying wage effects of offshoring: import- versus export-based measures of production fragmentation
PublikacjaIn this paper we examine the implications of international fragmentation of production on wages in the light of recent methodological developments in offshoring measurement. In particular, we compare the results stemming from two ways of quantifying offshoring – the traditional one based on import statistics and the one obtained from the decomposition of gross exports and input-output information. In the empirical part of our study,...
-
Evaluation of applicability of classic methods of a fault loop impedance measurement to circuits with residual current devices
PublikacjaMeasurement of fault loop impedance in low voltage grids and systems is in most cases performed to verify the effectiveness of protection against electric shock by automatic disconnection of supply. For the sake of measurement accuracy, it is advisable to perform it using large current. Unfortunately, in circuits with residual current devices which are very widely used nowadays, a large measurement current may trigger those devices...
-
Influence of temperature and nitrogen pressure on the test without active gases for high-temperature proton exchange membrane fuel cells
PublikacjaHigh-Temperature Proton-Exchange Membrane Fuel Cells (HT-PEMFCs) are a candidate for electrical energy supply devices in more and more applications. Most notably in the aeronautic industry. Before any use, an HT-PEMFC is preheated and after that supplied with its active gases. Only at this state, the diagnostics can be performed. A method of testing not requiring a complete start-up would be beneficial for many reasons. This article...
-
Hydraulic resistance analyses of selected elements of the prototype Stirling engine
PublikacjaThe paper presents the results of simulation tests of hydraulic resistance and temperature distribution of the prototype Stirling alpha engine supplied with waste heat. The following elements were analyzed: heater, regenerator and cooler. The engine uses compressed air as a working gas. Analyses were carried out for three working pressure values and different engine speeds. The work was carried out in order to optimize the configuration...
-
Automation of the Road Gate Operations Process at the Container Terminal—A Case Study of DCT Gdańsk SA
PublikacjaThe future increased terminal capacity will result in more container movement through the road complex and rail siding, which are one of the most critical areas (potential bottlenecks) in the container terminal. Truck turnaround time is one of the major factors that customers take into account while deciding how many container volumes they will handle through the container terminal. To enable to optimize increased traffic with...
-
Impacts of Using Exhaust Gas Recirculation and Various Amount of Dimethyl Ether Premixed Ratios on Combustion and Emissions on a Dual-Fuel Compression Ignition Engine
PublikacjaIn the presented research, the authors dealt with the specific properties of the combustion process of dimethyl ether (DME) in a combustion car (Volkswagen Golf IV) engine AJM 1.9 TDI PDE made by Volkswagen factory. Dimethyl ether is an alternative fuel produced most often from natural gas, which can be used in compression ignition engines as a single fuel or co-burned with diesel oil. This work describes the impacts of using exhaust...
-
Modeling lubricant flow between thrust-bearing pads
PublikacjaInlet temperature is one of the main inputs in all models for the analysis of fluid film bearing performance. At the same time, inlettemperature distribution and also oil velocity distribution at the inlet are the result of flow phenomena in the gap between the bearingpads. These phenomena are complex and in many cases further affected by any special arrangements of forced oil supply to the gapbetween pads. The reason for such...
-
Five-phase induction motor drive with sine-wave filter
PublikacjaThe paper presents closed loop ac drive with 5 phase induction motor operating with voltage source inverter and sine wave filter. The motor supply voltages and currents have sinusoidal shape. For well known adjustable electric drives the field oriented control method with flux and speed co ntrol can be applied. In the presence of output filter both control and estimation algorithms should be modified due to sine wave filter installation....
-
Design thinking qualifications framework – standardizing the innovative approach to entrepreneurial education delivery to engineering students
PublikacjaHighly competitive labor market stimulates increasing expectations towards fresh university alumni. It is not enough to be an expert - well educated and often experienced - in chosen discipline. High variability of the business environment, continuous change, number of risks, together with higher work demand than supply, shape clear employers’ expectations: entrepreneurial employees are wanted. On this ground a need for entrepreneurial...
-
Matching Exception Class Hierarchies between .NET, Java Environments
PublikacjaThe paper presents a methodology of exception classification and matching exception messages between .NET andJava environments. The methodology operates on existing exception class hierarchies and proposes two complementingapproaches: automated and manual matching. The automated matching uses the similarity measure to find associationsbetween exception messages from the two sets of classes for the considered programming languages....
-
Assessing groundwater vulnerability to pollution in the Puck region (denudation moraine upland) using vertical seepage method
PublikacjaDegradation of groundwater quality can cause a serious water supply and environmental problems. The identify of potential groundwater pollution can be determined by assessment of groundwater vulnerability method. The assessment of groundwater vulnerability to pollution was based on estimation of migration time of potential conservative contamination through the vadose zone. Area of investigation is a type of denudation moraine...
-
Comparison of Downdraft and Updraft Gasification of Biomass in a Fixed Bed Reactor
PublikacjaThe aim of this study was to compare and analyze the gasification process of beech wood. The experimental investigation was conducted inside a gasifier, which can be operated in downdraft and updraft gasification system. The most important operating parameter studied in this paper was the influence of the amount of supply air on the temperature distribution, biomass consumption and syngas calorific value. The results show that...
-
A novel methodology for the enantiomeric resolution of methamphetamine, its precursors and intermediates by GC-MS
PublikacjaImpurity profiling and classification of abused drugs using chiral analytical techniques is of particular interest and importance because of the additional information obtained from this approach. When these methods are applied to the synthesis of illicitly used substances, they can supply valuable information about the conditions/chemicals used in the synthesis. In this study, simultaneous chiral separation of methylamphetamine,...
-
Elective Project II: MOVABLE HOUSE – the home of a Modern Nomad
Kursy OnlineAs part of the elective seminar, students working in groups of 3 people will prepare architectural and lighting concept for an international competition: "MOVABLE HOUSE – The Home of a Modern Nomad " organized by the Polish Lighting Industry Association), co-organized by Goczołowie Architekci OVO Grąbczewscy Architects and the SOMA Agency, the organizer of the International LIGHT Fair. More information here about the competition...
-
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,...
-
Use of Neural Networks in Diagnostics of Rolling-Element Bearing of the Induction Motor
PublikacjaBearing defect is statistically the most frequent cause of an induction motor fault. The research described in the paper utilized the phenomenon of the current change in the induction motor with bearing defect. Methods based on the analysis of the supplying current are particularly useful when it is impossible to install diagnostic devices directly on the motor. The presented method of rolling-element bearing diagnostics used indirect...
-
Analytical method for calculation of heat source temperature drop for the Organic Rankine Cycle application
PublikacjaIn the paper presented are considerations on the cooperation of the limited capacity heat source with the Organic Rankine Cycle unit. Usually the heat source providing thermal energy to the Organic Rankine Cycle (ORC) may have twofold characteristics. It can be in the form of a single phase fluid, i.e. as hot exhaust gas or hot liquid, or in some cases it may be available as a phase changing fluid, as for example, technological...
-
Multiple output CMOS current amplifier
PublikacjaIn this paper the multiple output current amplifier basic cell is proposed. The triple output current mirror and current follower circuit are described in detail. The cell consists of a split nMOS differential pair and accompanying biasing current sources. It is suitable for low voltage operation and exhibits highly linear DC response. Through cell devices scaling, not only unity, but also any current gains are achievable. As...
-
Swarm-Assisted Investment Planning of a Bioethanol Plant
PublikacjaBioethanol is a liquid fuel for which a significant increase in the share of energy sources has been observed in the economies of many countries. The most significant factor in popularizing bioethanol is the profitability of investments in construction of facilities producing this energy source, as well as the profitability of its supply chain. With the market filled with a large amount of equipment used in the bioethanol production...