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Search results for: ELECTROHYDRODYNAMIC PUMP
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Chemical Theory of Machines, basic principles of strength with examples of calculations
PublicationThis book encompasses the essential range of information on technical aspects of mechanical design. It was written primarily for the students and staff of chemistry faculties of technical universities, yet it may also be utilized by everyone, who ether would like to try or already enjoys designing, but cannot take advantage of typical stress & machine construction handbooks. These handbooks often require familiarity with the concepts...
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Research on water lubricated main shaft bearings in conditions of improper lubrication and cooling conducted on high torque real-life scale bush test rig
PublicationWater lubricated polymer bushes find increasingly popular use in the sliding bearings of marine propellers, water turbines and pump shafts. Such popularity is partly due to their simple construction which also means relatively affordable price. In addition, properly designed and installed water lubricated bearings may well last for over a decade. However, in practical experience one may also observe cases of rapid wear...
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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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Numerical analysis of vacuum drying of a porous body in the integrated domain
Publicationn the present study, the vacuum drying process of an apple slice is numerically modeled based on a control volume method. Transient two-dimensional Navier– Stokes, energy, moisture, and Luikov equations are solved by numerical coding (Fortran) to simulate the simultaneous heat and mass transfer in the ambient and apple slice, respectively. The privilege of using Luikov's model is that the capillary forces are considered, and a...
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Nadzór naukowo-techniczny nad pracą i stanem podłoża gruntowego pod kątem wpływu na konstrukcję budynków z uwzględnieniem funkcjonowania systemu odwodnienia i problematyki kanalizacji głębokiej wraz z niezbędnymi opracowaniami dokumentacyjnymi i badaniami geodezyjnymi w Elektrowni Ostrołęka. Sprawozdanie za pierwsze półrocze 2016 roku
PublicationNiniejsze opracowanie stanowi półroczne sprawozdanie z nadzoru geotechnicznego i geodezyjnego prowadzonego w celu przeciwdziałania zagrożeniom stateczności wybranych obiektów na skutek zmian położenia zwierciadła wody gruntowej pod fundamentami budynków na terenie Elektrowni Ostrołęka, z nawiązaniem do analiz z lat poprzednich pozwalających na określenie trendów długookresowych. W pierwszym półroczu 2016 roku kontynuowano pomiary...
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Nowe rozwiązania w hydraulice przemysłu maszynowego - prace badawcze w Katedrze Hydrauliki i Pneumatyki
PublicationW referacie przedstawiono osiągnięcia Katedry Hydrauliki i Pneumatyki Politechniki Gdańskiej.W chwili obecnej uruchamiana jest produkcja pomp wielotłoczkowych PWK o stałej wydajności. Strategicznym celem jest zbudowanie jednostek o zmiennej wydajności. Hydrostatyczne zrównoważenie mechanizmu rozrządu pozwala bowiem zrealizować unikalny w skali światowej mechanizm bezpośredniego sterowania wydajnością pompy za pomocą elementu o...
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Zakład Hydrauliki i Pneumatyki
Research TeamsPrace badawcze i rozwojowe pomp wyporowych, silników hydraulicznych i zaworów z zastosowaniem oleju mineralnego i wody jako cieczy roboczych.
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RuAl6—An Endohedral Aluminide Superconductor
PublicationSuperconductivity is reported in an endohedral aluminide compound, RuAl6, with Tc = 1.21 K. The normalized heat capacity jump at Tc, ΔC/γTc = 1.58, confirms bulk superconductivity. The Ginzburg–Landau parameter of κ = 9.5 shows that RuAl6 is a type-II superconductor. Electronic structure calculations for RuAl6 are explored in comparison to its structural analogue ReAl6 (Tc = 0.74 K). The stability of the phases is discussed in...
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Load testing of a suspended footbridge in Radom (Poland)
PublicationThe footbridge in Radom is a suspended bridge of an interesting architectural form. The structure was de-signed for 4 kN/m2 of crowd loading. Dynamic calculations were not included in the design. The structure’s acceptance tests took place on the 14th of October 2016. The behaviour of the footbridge in static testing met the expectations. Unfortunately, as a result of dynamic tests, dangerous behaviour of the footbridge was revealed....
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Non-Destructive Testing of a Sport Tribune under Synchronized Crowd-Induced Excitation Using Vibration Analysis
PublicationThis paper presents the concept of repairing the stand of a motorbike speedway stadium. The synchronized dancing of fans cheering during a meeting brought the stand into excessive resonance. The main goal of this research was to propose a method for the structural tuning of stadium stands. Non-destructive testing by vibration methods was conducted on a selected stand segment, the structure of which recurred on the remaining stadium...
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Pumps, Turbines and Small Hydropower, LEC/LAB, ET, sem.7 winter 2022/23 (PG_00042108)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, ET, sem.7 winter 2023/24 (PG_00042108)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Mechanisms of azole resistance among clinical isolates of Candida glabrata in Poland
PublicationCandida glabrata is currently ranked as the second most frequently isolated aetiological agent of human fungal infections, next only to Candida albicans. In comparison with C. albicans, C. glabrata shows lower susceptibility to azoles, the most common agents used in treatment of fungal infections. Interestingly, the mechanisms of resistance to azole agents in C. albicans have been much better investigated than those in C. glabrata....
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Correlation between the number of Pro-Ala repeats in the EmrA homologue of Acinetobacter baumannii and resistance to netilmicin, tobramycin, imipenem and ceftazidime
PublicationAcinetobacter baumannii coccobacilli are dangerous to patients in intensive care units because of their multidrug resistance to antibiotics, developed mainly in the past decade. This study aimed to examine whether there is a significant correlation between the number of Pro-Ala repeats in the CAP01997 protein, the EmrA homologue of A. baumannii, and resistance to antibiotics. A total of 79 multidrug-resistant A. baumannii strains...
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Magnetic field mapping along a NV-rich nanodiamond-doped fiber
PublicationIntegration of NV−-rich diamond with optical fibers enables guiding quantum information on the spin state of the NV− color center. Diamond-functionalized optical fiber sensors have been demonstrated with impressive sub-nanotesla magnetic field sensitivities over localized magnetic field sources, but their potential for distributed sensing remains unexplored. The volumetric incorporation of diamonds into the optical fiber core allows...
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Komputerowa analiza odkształceń i naprężeń elementów hydraulicznych silników satelitowych typoszeregu sm przy wykorzystaniu metody elementów skończonych
Publicationopisano modelowanie i symulację komputerową nowego typu hydraulicznych silników satelitowych o małych objętościach roboczych. analizy mes ukierunkowane były na ocenę odkształceń i stanu naprężeń poszczególnych elementów silników. pozwoliły one na zwiększenie dopuszczalnego ciśnienia pracy oraz poprawę sprawności całkowitej.prace zostały wykonane w katedrze hydrauliki i pneumatyki politechniki gdańskiej w ramach projektu badawczo-rozwojowego...
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Selecting Features with SVM
PublicationA common problem with feature selection is to establish how many features should be retained at least so that important information is not lost. We describe a method for choosing this number that makes use of Support Vector Machines. The method is based on controlling an angle by which the decision hyperplane is tilt due to feature selection. Experiments were performed on three text datasets generated from a Wikipedia dump. Amount...
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Eksploatacja napędów hydraulicznych w niskich temperaturach otoczenia. Część IV : Analiza procesów nagrzewania zespołów hydraulicznych w warunkach szoku termicznego
PublicationW artykule przeanalizowano procesy nagrzewania zespołów hydraulicznych w warunkach szoku termicznego. Przedstawione bilanse ciepła dla zespołów hydraulicznych: pomp i silników oraz rozdzielaczy suwakowych pokazują jakie parametry, własności i współczynniki należy uwzględniać przy analizie ich nagrzewania. Nieustalone procesy nagrzewania elementów zespołów hydraulicznych wpływają znacząco na ich działanie, gdyż oddziałują na luzy...
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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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Superconductivity–Electron Count Relationship in Heusler Phases─the Case of LiPd2Si
PublicationWe report superconductivity in the full Heusler compound LiPd2Si (space group Fm3̅m, No. 225) at a critical temperature of Tc = 1.3 K and a normalized heat capacity jump at Tc, ΔC/γTc = 1.1. The low-temperature isothermal magnetization curves imply type-I superconductivity, as previously observed in LiPd2Ge. We show, based on density functional theory calculations and using the molecular orbital theory approach, that while LiPd2Si...
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Marine propeller shaft bearings under low-speed conditions: water vs. oil lubrication
PublicationThe bearings used in shipbuilding, hydropower, and water pumps have undergone a metamorphosis in recent decades. Because of environmental regulations, lubrication with grease or mineral oil is prohibited. Thus, the standard solutions include water-lubricated bearings with polymer bushings or sealed systems lubricated with oil. When properly designed, assembled, and operated, bearings can operate reliably for years. However, specific...
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Pumps, Turbines and Small Hydropower, LEC/LAB, DaPE, sem.5 winter 2022/23 (M:320403W0)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, DaPE, sem.5 winter 2023/24 (M:320403W0)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Odzysk energii ze ścieków na przykładzie wybranych oczyszczalni komunalnych
PublicationPrzedmiotem pracy jest analiza procesów związanych z pozyskiwaniem i wykorzystaniem zasobów energii pochodzących ze ścieków w oczyszczalniach komunalnych. Badaniom poddano zarówno substraty (ścieki surowe) jak i produkty oczyszczania (osady ściekowe, ścieki oczyszczone). Ścieki surowe i oczyszczone analizowano pod kątem przydatności jako zasobów ciepła odpadowego. Osady ściekowe traktowano jako wyodrębnioną ze ścieków organiczno-mineralną...
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Wyznaczanie i symulacje sytuacji miarodajnych przy wymiarowaniu kanalizacji ciśnieniowej
PublicationOmówiono starannie wypracowaną metodę wymiarowania kanalizacji ciśnieniowej. Istotnymi elementami metody są poszukiwania opisów trzech różnych grup charakterystycznych sytuacji eksploatacyjnych w projektowanym systemie. Są to: (1) sytuacje miarodajne z punktu widzenia rozmiarów ewentualnego uderzenia hydraulicznego, (2) sytuacje miarodajne dla zapewnienia wymaganych warunków samooczyszczania, (3) sytuacje miarodajne dla doboru...
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Multiobjective Water Distribution Systems Control of Pumping Cost, Water Quality, and Storage-Reliability Constraints
PublicationThis work describes a multiobjective model for trading-off pumping cost and water quality for water distribution systems operation. Constraints are imposed on flows and pressures, on periodical tanks operation, and on tanks storage. The methodology links the multiobjective SPEA2 algorithm with EPANET, and is applied on two example applications of increasing complexity, under extended period simulation conditions and variable energy...
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Nowe rozwiązanie kompensacji luzów osiowych w silnikach satelitowych o małych objętościach roboczych
PublicationOpisano modelowanie i symulację komputerową nowego typu hydraulicznych silników satelitowych o małych objętościach roboczych. analizy miały na celu dobór parametrów konstrukcyjnych wpływających na odkształcenia węzła kompensacji luzów osiowych. dzięki przeprowadzonym badaniom znacznie zmniejszono odkształcenia płyt kompensacyjnych co pozwoliło na podniesienie dopuszczalnego ciśnienia pracy oraz poprawę sprawności całkowitej.prace...
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Recommendations for Urban Freight Policy Development in Gdynia
PublicationThe purpose of this paper was to provide practical recommendations on how to develop Gdynia’s urban freight policy based on actual planning experience and characteristics of potential measures. Freight policy scheme was developed as a result of three interrelated factors: a) the general procedure of the urban freight planning, b) the city's current planning stage analysis and, c) characteristics of urban freight objectives and...
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Superconductivity in the intermetallic compound Zr5Al4
PublicationPolycrystalline Zr5Al4 was synthesized using the arc-melting method. Powder X-ray diffraction confirms the previously reported crystal structure of the Ti5Ga4-type P63/mcm with lattice parameters: a = 8.4312(6) A , and c = 5.7752(8) A . Electrical resistivity and low-temperature magnetic susceptibility measurements indicate that Zr5Al4 exhibits superconducting behavior below 2 K. The normalized heat capacity jump at Tc= 1.82 K...
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Load effect impact on the exploitation of concrete machine foundations used in the gas and oil industry
PublicationMachine foundations is a critical topic in the gas and oil industry, which design and exploitation require extensive technical knowledge. Machine foundations are the constructions which are intended for mounting on it a specific type of machine. The foundation has to transfer dynamic and static load from machine to the ground. The primary difference between machine foundations and building foundations is that the machine foundations...
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The experimental results of diesel fuel spray with marine engine injector
Open Research DataThe data set presents the measurement of the diesel fuel spray from with marine engine injector. The main target presents results is a study of the time course of macro parameters (spray tip penetration, spray cone angle) of fuel spray in the cylinder of marine diesel engine. The impact of ambient conditions and the geometrical parameters of the injector...
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Force-deformation spectroscopy in contact mode
Open Research DataThe deformation-distance spectroscopic curve is obtained by registering the value of the probe cantilever deflection as a function of the elongation of the piezoelectric scanner. It assumes a simple relationship in the form of Hooke’s law, linking the deformation of the lever with the amount of its deflection caused by the proximity of the probe and...
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Examination of fresh water chemistry in maritime Antarctica during austral summer 2017
PublicationDue to the fact that Antarctica is one of the least polluted places on Earth, it is a perfect place to observe the spread of global pollution. Therefore, research conducted on this continent is important due to the possibility of investigating the type of pollution and their way of transport. This work considers presence of organic contaminants in Maritime Antarctica in unexplored until now, Lions Rump headland. Qualitative and...
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Pressure drop and heat transfer during boiling and condensation at subcritical region
PublicationMost of the data presented in the literature relate to saturation temperatures in the range - 20°C to 40°C due to the application in refrigeration technology. There is necessity to extend databases to higher values of saturation temperature due to new applications such as Organic Rankine Cycle and high temperature heat pumps. Only few papers contain data for high reduced pressure for low boiling point liquids. This paper focus...
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EXPERIMENTAL RESEARCH ON INFLUENCE OF THE FUEL NOZZLE GEOMETRY ON THE FUEL CONSUMPTION OF THE MARINE 4-STROKE DIESEL ENGINE
PublicationThe article presents experimental research that has been carried out on a marine, 4-stroke, 3-cylinder, turbocharged engine. During testing, the engine operated at a constant rotational speed of 750 rpm and a load from 0 kW to 280 kW. The engine was fuelled by diesel oil of known specification and loaded by electric generator with water resistance. The fuel consumption was measured during the engine operation with fuel nozzles...
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Evaluati on of long-term start up costs impact on short-term price based operational optimization of a CCGT using MILP
PublicationAn increasing share of the weather-dependent RES generation in the power system leads to the growing importance of flexibility of conventional power plants. They were usually designed for base load operation and it is a challenge to determine the actual long-term cycling costs, which account for an increase in maintenance and overhaul expenditures, increased forced outage rates and shortened life expectancy of the plant and components....
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Multi-Objective Water Distribution Systems Control of Pumping Cost, Water Quality, and Storage-Reliability Constraints
PublicationThis work describes a multi-objective model for trading-off pumping cost and water quality for water distribution systems operation. Constraints are imposed on flows and pressures, on periodical tanks operation, and on tanks storage. The methodology links the multi-objective SPEA2 algorithm with EPANET, and is applied on two example applications of increasing complexity, under extended period simulation conditions and variable...
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Kombucha from alternative raw materials – The review
PublicationNowadays, people's awareness about the role of diet in maintaining well-being and good health has increased. Consumers expect that the products not only provide them with essential nutrients but will also be a source of biologically active substances, which are beneficial to their health. One of the "healthy trends," which has appeared among the consumers worldwide is kombucha, a tea drink with high antioxidant potential, obtained...
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Olmesartan for the Delay or Prevention of Microalbuminuria in Type 2 Diabetes
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Kriging metamodels and design re‐utilization for fast parameter tuning of antenna structures
PublicationThe paper addresses the problem of computationally efficient electromagnetic (EM)‐driven design closure of antenna structures. The foundations of the presented approach are fast kriging interpolation metamodels, utilized for two purposes: (a) producing a good starting point for further parameter tuning, and (b) yielding a reasonable Jacobian matrix estimate to jump‐start the optimization procedure. The models are rendered using...
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Potential of novel atomic emission techniques as a tool for investigation of the possibilities of using industrial waste as additives in construction materials
PublicationNowadays, due to the global ecological crisis and ways to prevent a climate disaster, more and more attention is paid to green techno-logies and green Chemistry, which are part of the so-called “The Green Deal.” The main assumption is the optimization of the processes of producing necessary goods and the implementation of methods of managing postproduction waste in the least environmentally harmful manner. In the presented research,...
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ANALIZA STANU TECHNICZNEGO RUROCIĄGÓW: WODY PRZeMYSŁOWEJ I SOLANKI
PublicationPracę 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...
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Semi-Markovian models of the process of technical state changes of technical objects.
PublicationNajistotniejszym problemem eksploatacji wszystkich obiektów technicznych (urządzeń) jest problem racjonalnego (a zwłaszcza optymalnego) decyzyjnego sterowania procesem zmian stanów technicznych tych obiektów. Sterowanie takie może być realizowane w przypadku zastosowania między innymi modelu wspomnianego procesu zmian stanów. Mając to na uwadze, w opracowaniu tym przedstawiono formalny opis procesu eksploatacji obiektów technicznych...
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Rezultaty badań rozwojowych hydraulicznych silników satelitowych typoszeregu SM
PublicationOpisano najnowszą konstrukcję hydraulicznych silników satelitowych typoszeregu SM, o małych objętościach roboczych od 5-34cm3/obr. Przedstawiono wyniki badań laboratoryjnych jednego, wybranego z typoszeregu, silnika zasilanego olejem, emulsją oleju w wodzie typu HFA-E oraz wodą. Ze względu na jednakową konstrukcję wszystkich silników typoszeregu sprawności tych silników przyjmują podobne wartości. Porównano również silniki satelitowe...
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Rezultaty badań rozwojowych hydraulicznych silników satelitowych typoszeregu SM
PublicationOpisano najnowszą konstrukcję hydraulicznych silników satelitowych typoszeregu SM, o małych objętościach roboczych od 5-34cm3/obr. Przedstawiono wyniki badań laboratoryjnych jednego, wybranego z typoszeregu, silnika zasilanego olejem, emulsją oleju w wodzie typu HFA-E oraz wodą. Ze względu na jednakową konstrukcję wszystkich silników typoszeregu sprawności tych silników przyjmują podobne wartości. Porównano również silniki satelitowe...
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SYMULACJA PRACY GRUNTOWEGO WYMIENNIKA CIEPŁA - UŻYCIE METOD NUMERYCZNYCH
PublicationArtykuł poświęcony jest zagadnieniu wykorzystania symulacji numerycznych do projektowania GWC( Gruntowego Wymiennika Ciepła). W artykule opisano różne rodzaje gruntowych wymienników ciepła. Aparaty te używane są do wykorzystania pojemności cieplnej gleby w połączeniu z pompą ciepła dla zwiększenia ich skuteczności. Jedno, dwu i trój wymiarowe modele obliczeniowe procesu wymiany ciepła znaleźć można w literaturze. Modele symulacyjne...
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Superconductivity in CaBi2
PublicationSuperconductivity is observed with critical temperature Tc = 2.0 K in self-flux-grown single crystals of CaBi2. This material adopts the ZrSi2 structure type with lattice parameters a = 4.696(1) Å, b = 17.081(2) Å and c = 4.611(1) Å. The crystals of CaBi2 were studied by means of magnetic susceptibility, specific heat and electrical resistivity measurements. The heat capacity jump at Tc is DC/gTc = 1.41, confirming bulk superconductivity;...
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Greenhouse control system design
PublicationCoraz większa populacja i zmniejszające się tereny uprawne wymusza efektywniejsze metody uprawy roślin. Zaradzić temu mogą układu hydroponiczne, które dzięki rozwojowi techniki są w stanie osiągać znacznie większe oraz bardziej jednorodne plony. Jest to możliwe dzięki zaawansowanym systemom opartym na dokładnych urządzeniach pomiarowych, sterowaniu w zamkniętej pętli oraz mikrokontrolerom umożliwiającym...
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Audible noise in ship’s electrical drive systems with frequency converters
Open Research DataThe presented dataset is part of research focusing on the impact of the ship's electrical drive systems with frequency converters on vibrations and the level of audible noise on ships.
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Immittance Studies of Bi6Fe2Ti3O18 Ceramics
PublicationResults of studies focusing on the electric behavior of Bi6Fe2Ti3O18 (BFTO) ceramics are reported. BFTO ceramics were fabricated by solid state reaction methods. The simple oxides Bi2O3, TiO2, and Fe2O3 were used as starting materials. Immittance spectroscopy was chosen as a method to characterize electric and dielectric properties of polycrystalline ceramics. The experimental data were measured in the frequency range D = (101–107)...