Filtry
wszystkich: 2228
-
Katalog
- Publikacje 1987 wyników po odfiltrowaniu
- Czasopisma 11 wyników po odfiltrowaniu
- Osoby 33 wyników po odfiltrowaniu
- Projekty 3 wyników po odfiltrowaniu
- Laboratoria 1 wyników po odfiltrowaniu
- Kursy Online 35 wyników po odfiltrowaniu
- Wydarzenia 5 wyników po odfiltrowaniu
- Dane Badawcze 153 wyników po odfiltrowaniu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: FREDHOLM OPERATOR
-
Redesign of the Research Platform for Monitoring, Control and Security of Critical Infrastructure Systems
PublikacjaCritical Infrastructure Systems (CISs) play a key role in modern societies. Their sustainable operation depends heavily on the performance of dedicated structures and algorithms targeting monitoring, control and security aspects. In previous work a Research Platform (RP) for the design and simulation of such systems was presented. This works updates the information on the RP through the description of major hardware and software...
-
A method for evaluating durability of porous slide bearings
PublikacjaThe article presents the structures of porous bearings bushes and greasy lubricants, and the similarity criterion resulting from this structures. A phisical model is proposed which describes the operation of the porous slide bearing bush taking into account, via analogy, the phenomena taking place in the grease lubricant nodes instead of those observed in the bush structures.Included are the result of experimental tests of three...
-
A Method of MOS Evaluation for Video Based Services
PublikacjaThis paper deals with a method for QoE evaluation for the services transmitting large amount of data perceived by the end user in relatively short time periods, e.g. streaming video in mobile operator...
-
Call Processing Performance in a Multidomain IMS/NGN with Asymmetric Traffic
PublikacjaIn this paper we continue our research using the previously proposed analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). The aim of the model is to assess mean Call Set-up Delay (CSD) and mean Call Disengagement Delay (CDD), which are standardized call processing performance parameters. The output variables...
-
Modelling and Analysis of the Positioning Accuracy in the Loading Systems of Mobile Cranes
PublikacjaIn this work, the authors analyse the influence of the order and range of sequential movements of a crane's working members on the accuracy of the final cargo positioning. The analysis was conducted on the basis of a specially developed method in which the authors proposed the introduction of a geometrical indicator of positioning the load in the intermediate positions (after completing each movement sequence) and in the target...
-
Risks associated with the transportation of hazardous materials on public roads
PublikacjaA significant proportion of the transport of hazardous materials is carried out on public roads. Therefore, the safety of such transport is becoming increasingly important. Every catastrophe involving hazardous materials has a negative impact on direct road users and the surrounding environment, becauses its range is mostly not local. It follows that in the event of such catastrophe, its effects should be minimized. This is possible...
-
Quantum privacy witness
PublikacjaWhile it is usually known that the mean value of a single observable is enough to detect entanglement or its distillability, the counterpart of such an approach in the case of quantum privacy has been missing. Here we develop the concept of a privacy witness, i.e., a single observable that may detect the presence of the secure key even in the case of bound entanglement. Then we develop the notion of secret-key estimation based...
-
Should we seek further improvement of fluid film bearings - what for and how?
PublikacjaFluid film bearings have been extensively used in the industry because of their unbeatable durability and extremely low friction coefficient. Large bearings supporting shafts of huge and important rotating machines constitute a special group of fluid film bearings since the reliability of crucial systems, like for example electro-energetic system, rely on their trouble-free operation. Large thrust bearings, apart from enormous...
-
Autonomous port management based AGV path planning and optimization via an ensemble reinforcement learning framework
PublikacjaThe rapid development of shipping trade pushes automated container terminals toward the direction of intelligence, safety and efficiency. In particular, the formulation of AGV scheduling tasks and the safety and stability of transportation path is an important part of port operation and management, and it is one of the basic tasks to build an intelligent port. Existing research mainly focuses on collaborative operation between...
-
The Impact of Material Selection on Durability of Exhaust Valve Faces of a Ship Engine – A Case Study
Publikacjawo alloys were used in order to extend the service life of marine engine exhaust valve head. Layers of cobalt base alloys were made of the powders with with chemical composition as follow: the layer marked L12; C-1,55%; Si-1,21%; Cr-29,7%; W-9%; Ni-2%; Mo<0,01%; Fe-1,7%; Co-54,83% and the layer marked N; C-1,45%; Co-38,9%; Cr-24,13%; Ni-10,43%; W-8,75%; Fe-7,64%; Mo-7,56%; Si-2,59%. Base metal was valve steel after heat treatment....
-
Surface modifcation of PMMA polymer detected by XPS
Dane BadawczeIn order to obtain the experimental specimens, four PMMA/PC61BM samples with the following mass proportions were prepared: 10%, 20%, 30%, and 40%. In addition, as a reference, a PMMA sample without PC61BM was prepared as well. For the fabrication process, PC61BM 99.5% (Solenne BV), chloroform HPLC (Sigma Aldrich), and PMMA (commercially available...
-
Sebastian Wilczewski dr inż.
OsobyDr inż. Sebastian Wilczewski jest zatrudniony na stanowisku adiunkta w Katedrze Zastosowań Informatyki w Zarządzaniu, Wydział Zarządzania i Ekonomii. Ponadto od ponad 20 lat pracuje w firmach informatycznych, gdzie zajmował stanowiska od inżyniera i konsultanta, poprzez stanowisko Project Managera, Portfolio Manager i Proces Ownera aż do stanowiska Team Leadera dla zespołu około 30 analityków IT. Zdobytą wiedzą i doświadczeniem...
-
Recycling of Photovoltaic Solar Cells and Modules - Te State - Of - Art
PublikacjaIn comparison to other energy producing techniques, photovoltaics (PV) is one of the most promising options: no emission of any matter into the environment during operation; extremely long operation period (estimated average: 25 years), minimum maintenance, robust technique, aesthetic aspects. The use of photovoltaics is rapidly increasing, and the respective market is developing accordingly. Although PV manufacturing equipment...
-
CURRENT TRENDS IN RECYCLING OF PHOTOVOLTAIC SOLAR CELLS AND MODULES WASTE
PublikacjaIn comparison to other energy producing techniques, photovoltaics (PV) is one of the most promising options: no emission of any matter into the environment during operation; extremely long operation period (estimated average: 25 years), minimum maintenance, robust technique, aesthetic aspects. The use of photovoltaics is rapidly increasing, and the respective market is developing accordingly. Although PV manufacturing equipment...
-
Partial inhibition of borohydride hydrolysis using porous activated carbon as an effective method to improve the electrocatalytic activity of the DBFC anode
PublikacjaCarbon materials are commonly used catalyst supports in various types of fuel cells. Due to the possibility of designing their properties, they seem to be attractive and functional additives. In Direct Borohydride Fuel Cells (DBFCs), the electrooxidation reaction of borohydride competes with the undesirable hydrolysis reaction, therefore our work aimed to modify anodes based on a multi-component hydrogen storage alloy with a small...
-
Investigation of the Combustion Processes in the Gas Turbine Module of an FPSO Operating on Associated Gas Conversion Products
PublikacjaIn this paper, we consider the issue of thermo-chemical heat recovery of waste heat from gas turbine engines for the steam conversion of associated gas for offshore vessels. Current trends in the development of offshore infrastructure are identified, and the composition of power plants for mobile offshore drilling units and FPSO vessels is analyzed. We present the results of a comparison of power-to-volume ratio, power-to-weight...
-
All-gather Algorithms Resilient to Imbalanced Process Arrival Patterns
PublikacjaTwo novel algorithms for the all-gather operation resilient to imbalanced process arrival patterns (PATs) are presented. The first one, Background Disseminated Ring (BDR), is based on the regular parallel ring algorithm often supplied in MPI implementations and exploits an auxiliary background thread for early data exchange from faster processes to accelerate the performed all-gather operation. The other algorithm, Background Sorted...
-
The thermal effort during marine steam turbine flooding with water
PublikacjaThe work discussed an extreme case of cooling a steam turbine. The ship's steam turbine was used as an example. In marine transport units with low-speed engines dominate, however, there are also units with steam turbines. An example of analysed marine steam turbine is shown in Fig. 1. When considering the issue of cooling steam turbines, it is necessary to estimate the extreme conditions that may occur during operation of the turbine....
-
Problemy edukacji technicznej
PublikacjaNa jakość wyrobów istotny wpływ ma działanie człowieka w całym procesie ich powstawania. Wskazano na związek działania każdego systemu technicznego z poziomem wykształcenia człowieka - inżyniera, jako twórcy i operatora tego systemu. Omówiono główne problemy związane z kształceniem w zakresie przedmiotów technicznych oraz dokonano analizy różnorodnych form oddziaływania na słuchacza w procesie tego kształcenia. Przedstawiono niektóre...
-
Multiresolution analysis and adaptive estimation on a sphere using stereographic wavelets
PublikacjaWe construct an adaptive estimator of a density function on d dimensional unit sphere Sd (d ≥ 2), using a new type of spherical frames. The frames, or as we call them, stereografic wavelets are obtained by transforming a wavelet system, namely Daubechies, using some stereographic operators. We prove that our estimator achieves an optimal rate of convergence on some Besov type class of functions by adapting to unknown smoothness....
-
Modelowanie, sterowanie i wizualizacja quadrocoptera
PublikacjaArtykuł przedstawia podejście do budowy modelu matematycznego quadrocoptera. Głównym celem budowy modelu było zaprojektowanie odpowiedniego sterowania obiektu oraz analiza jego zachowania się w różnych sytuacjach. Jako założenie przyjęto budowę modelu, systemu sterowania oraz wszelkich towarzyszących algorytmów w otwartym środowisku programistycznym, co pozwoli na późniejszą ich implementację w rzeczywistym obiekcie, bez konieczności...
-
Wykorzystanie rejestracji przebiegów szybkozmiennych do weryfikacji modeli dynamicznych KSE
PublikacjaW referacie przedstawiono koncepcję narzędzia pozwalającego na weryfikowanie parametrów modeli dynamicznych elementów KSE. Narzędzie wykorzystuje program obliczeniowy PSLF, stosowany powszechnie przez operatora systemu przesyłowego. Nowatorstwo polega na wykorzystaniu dodatkowej aplikacji (programu w systemie MS Windows), która steruje pracą programu obliczeniowego. Powstaje w ten sposób tandem wygodnego interfejsu użytkownika...
-
Wykorzystanie rejestracji przebiegów szybkozmiennych do weryfikacji modeli dynamicznych KSE
PublikacjaW referacie przedstawiono koncepcję narzędzia pozwalającego na weryfikowanie parametrów modeli dynamicznych elementów KSE. Narzędzie wykorzystuje program obliczeniowy PSLF, stosowany powszechnie przez operatora systemu przesyłowego. Nowatorstwo polega na wykorzystaniu dodatkowej aplikacji (programu w systemie MS Windows), która steruje pracą programu obliczeniowego. Powstaje w ten sposób tandem wygodnego interfejsu użytkownika...
-
History and Perspective of Treatment Wetland in Poland – Part One: Lesson learned
PublikacjaEarly implementation of treatment wetlands under supervision of the researchers from were quite promising. The constructed facilities ensured effective wastewater treatment and sludge dewatering. In the next years a number of treatment wetland s systems were constructed without following the designing principles and left without proper maintenance. In the consequence this lead to unsatisfactory treatment results. Investigations...
-
Comparison of active proximity radars for the wearable devices
PublikacjaTwo methods of object position and movement estimation in relation to the user of smart glasses were investigated. An active infrared and ultrasonic methods of the obstacle detection were presented and compared. Application of these methods depend on active transducers type (physical medium used), geometry and surface properties of detected objects and their movement direction and speed. In the article properties of both detectors...
-
Investigation of Transmit and Receive Characteristics of Laboratory Model for the Parametric Echosounder
PublikacjaInvestigation and operation of devices based on nonlinear interaction of high-intensity waves have been carried out for several decades. However, it is still a new tool to study the properties of the water environment and especially the upper layers of the seabed. This paper describes the results of tests of the new device that is intended to be applied for sounding underwater areas. The device has been designed and built in collaboration with...
-
Analysis of inductive power transfer systems for variable air gap and voltage supply frequency
PublikacjaThe paper describes an IPT system, by which electrical energy may be transmitted through a large air gap between coils without electrical connection. It presents theoretical and simulation analysis of IPT, which allows for supplying a receiver in the conditions of slow, in relation to the dynamics of power supply, changes in dimension of the air gap. The influence of frequency characteristics of the system on the possible selection...
-
Autorska implementacja systemu wymiany numera-cji telefonicznej pomiędzy operatorami voip
PublikacjaW pracy przedstawiono autorską implementację systemu wymiany numeracji. System został stworzony w technologii Java, wykorzystując otwarte rozwiązania bazodanowe MySQL oraz PostgreSQL. System został przetestowany dla kilku klientów/operatorów wykorzystujących pule z ponad milionem numerów telefonicznych. W pracy wykazano spełnienie podstawowych wymagań narzucanych na system, w szczególności czas odpowiedzi systemu informacji o numerze...
-
Analiza jakości baz geolokalizacyjnych numerów IP
PublikacjaW pracy określono wymagania geolokalizacyjne dla telefonii VoIP przy realizacji usług ratunkowych. Przedstawiono metodykę oraz wyniki badań komercyjnych baz geolokalizacyjnych. Do badań wykorzystano dane geolokalizacyjne uzyskane od operatorów. Wnioski wypływające z badań są pesymistyczne, a ocena jakości badanych baz pod kątem trafności geolokalizacji użytkowników telefonów VoIP znacznie odbiega od samooceny firm, które te bazy...
-
Metrological analysis of an computerized system of protection against electric shock in circuits with variable speed drives
PublikacjaDrive systems, that can be operated at variable speed, are equipped with power electronics converters. This causes distortion of the earth current, and consequently the need to take into account the use of proper protective devices in relation to earth current harmonics. This paper presents a system for protection against electric shock in circuits with power electronics converters and metrological analysis indicating the requirements...
-
Evaluation of bearing and journal damage in MAN 9L40-54 engines installed on M/V STENA SCANDINAVICA ferry
PublikacjaThe following report was requested by Remontowa Shiprepair Yard (RSY) S.A. in Gdansk ´ (contract no. 4/2018/EX/U, dated 13.02.2018) and prepared based on the materials received from RSY, two on-board inspections and the participation of the contractors in three conferences with RSY representativesi. The goal of the analysis performed by the experts of Gdansk University of Technology was ´ to determine the character of the bearing...
-
PROMOWANIE USUGI PRZELEWU NATYCHMIASTOWEGO BLUECASH W BANKACH SPÓŁDZIELCZYCH
PublikacjaCelem pracy jest prezentacja Systemu Płatności BlueCash, którego operatorem jest firma Blue Media S.A.. Wskazuje on również na charakterystykę usługi szybkiego przelewu. Celem szczegółowym jest wskazanie na formy promocji stosowane przez banki w celu poinformowania klientów o dostępności płatności natychmiastowych. Tytułem zebrania danych na temat form promocji, autor przeprowadził badanie ankietowe pośród banków uczestników systemu płatności.
-
Methodology of experimental research on efficiency of hydro-mechanical automatic gearbox
PublikacjaThe article shortly describes the design and principle of operation of the hydromechanical gearbox and presents the methodology and design of test stands used for testing hydromechanical proto-type gearbox developed at Technical University of Gdansk. The article presents an approach according to which, in order to obtain reliable measurement data, it is necessary to separate the tests of the hydraulic and mechanical parts of the...
-
Aktualne Problemy w Elektroenergetyce” – APE’19
WydarzeniaWydział Elektrotechniki i Automatyki Politechniki Gdańskiej, Katedra Elektroenergetyki zaprasza do udziału w XIX Konferencji Naukowej „Aktualne Problemy w Elektroenergetyce” – APE’19
-
Applications of Tensor Analysis in Continuum Mechanics
PublikacjaA tensor field is a tensor-valued function of position in space. The use of tensor fields allows us to present physical laws in a clear, compact form. A byproduct is a set of simple and clear rules for the representation of vector differential operators such as gradient, divergence, and Laplacian in curvilinear coordinate systems. The tensorial nature of a quantity permits us to formulate transformation rules for its components...
-
Solid Oxide Fuel Cells with Ni infiltrated perovskite anode
PublikacjaNiobium-doped strontium titanate was used as the anode for a solid oxide fuel cell. Electrolyte-supported cells were prepared with pure perovskite and composite perovskite–yttria–stabilized-zirconia (YSZ) anodes. Fuel cell tests demonstrated significant improvement in power density after infiltration with a small amount of Ni. The obtained values of power densities are comparable with conventional Ni/YSZ cermet anode. In addition,...
-
Determination of causes of accelerated local corrosion of austenitic steels in water supply systems
PublikacjaThis paper concerns an inspection of a water supply system, made of AISI 304 steel, which showed signs of local corrosion at the weld. Such corrosion caused material perforation after very short periods of operation. It was revealed that steel was sensitised during the welding process. It was also proven that chromium micro-segregation occurred in the alloy leading to galvanic cell formation which initialised the process of pitting...
-
Assessment of protective properties of rubber lining in absorbers of flue gas desulphurization systems.
PublikacjaResults of research on degradation of rubber lining which is the main protection of absorbers in flue gas desulphurization (FGD) systems were presented. The power plant where the system operated is lignite-fired. Owing to measurements using electrochemical impedance spectroscopy and gravimetric determination of water content in the lining, the areas of the system which are most exposed to degradation were shown. The results obtained...
-
Photovoltaic demonstration set up
PublikacjaThe use of photovoltaics is growing rapidly in the industry as well as households. Therefore, educating the public will help them understand solar cell technology, which is becoming more common in everyday life. This paper proposes a demonstrational set-up of photovoltaic panel for the purpose of science education. It was used in numerous outreach activities such as science fairs. Moreover, it proved to be a great tool for education...
-
Low voltage photovoltaic power system
PublikacjaThe use of photovoltaics is growing rapidly in the industry as well as households. Therefore, educating the public will help them understand solar cell technology, which is becoming more common in everyday life. This paper proposes a demonstrational set-up of photovoltaic panel for the purpose of science education. It was used in numerous outreach activities such as science fairs. Moreover, it proved to be a great tool for education...
-
Software modules and application layer's security structure of RSMAD
PublikacjaThe paper discusses the software modules of Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short RSMAD). The structure of the application layer of the system has also been analysed in details, including: purpose, structure and principles of operation of software modules constituting this system. In addition, the paper presents and discusses the structure of security of application layer...
-
Relieving the Measuring System of the Trailer for Tyre/Road Rolling Resistance Measurements from the Inertia Force
PublikacjaIn the article the principle of measuring of tyre/road rolling resistance tyres in road conditions applied in a special measuring trailer is presented. This trailer was built in Faculty of Mechanical Engineering at Gdansk University of Technology. The construction of two special devices used in this trailer was discussed. These devices eliminate the influence of some chosen confounding measurements factors such as: the inertia...
-
Wspieranie procesów windykacji przez systemy telefonii VoIP
PublikacjaW pracy oceniono możliwości budowy ekonomicznego, zautomatyzowanego systemu wspierającego procesy windykacji opartego o rozwiązania telefonii VoIP. Omówiono uwarunkowania techniczne realizacji takiego systemu, w szczególności zwrócono uwagę na odmienną jakość usług telefonii IP oferowaną przez różnych operatorów. Przedstawiono autorski system informatyczny wspierający windykację, omówiono ograniczenia jakie nałożono na system podczas...
-
Ewolucja systemu zaliczania metodą multimetringu w centralach telekomunikacyjnych.
PublikacjaPublikacja ta opisuje dziedziny ewolucji multimetringu. Ukazuje jak rozwijał się multimetring w przeszłości oraz oczekiwane kierunki jego rozwoju w niedalekiej przyszłości. Poniższy tekst może być pomocny dla deweloperów multimetringu oraz dla inżynierów systemowych by poznać ważne dziedziny multimetringu i móc się na nich skoncentrować. Może być również użyteczny dla operatorów sieciowych i dostawców usług na dzisiejszym...
-
Differential-algebraic systems with maxima
PublikacjaMetoda numeryczno-analityczna została zastosowana do układów równań różniczkowo-algebraicznych z operatorem maximum. Zakładając warunek Lipschitza na funkcje występujące w zagadnieniu pokazano, że ciąg iteracji prostych jest zbieżny do rozwiązania zagadnienia pomocniczego. Podano warunki dostateczne na istnienie rozwiązania problemu wyjściowego. Iteracje Seidla też były przedmiotem badań. W ostatniej części pracy był dyskutowany...
-
Modern Arrangement for Reduction of Voltage Perturbations
PublikacjaThe contents of this chapter encompass general problems and the most important issues of power-supply-quality improvement in AC systems. In the context of the above, consideration is given to evaluation of bilateral interactions of receivers with an electrical power-distribution system and methods of their reduction. Also are discussed the basis of operation of the most important compensation-filtration devices and their applications...
-
On the preestimation technique and its application to identification of nonstationary systems
PublikacjaThe problem of noncausal identification of a nonstationary stochastic FIR (finite impulse response) sys- tem is reformulated, and solved, as a problem of smoothing of preestimated parameter trajectories. Three approaches to preestimation are critically analyzed and compared. It is shown that optimization of the smoothing operation can be performed adaptively using the parallel estimation technique. The new approach is computationally...
-
Computer-aided analysis of resonance risk in power system with Static Var Compensators
PublikacjaStatic Var Compensators operation in a power system may significantly improve voltage profiles in nodes and the reactive power balance, as well as ensure greater system stability in emergency conditions. However these devices may be a cause of a resonance in the system. The aim of this paper is to call attention to the need to include resonance phenomena in a compensator’s location evaluation process. The analysis performed in...
-
Control of a vapour microturbine set in cogeneration applications
PublikacjaSystems with microturbines are implemented for local generation of heat and electricity. This paper presents the analysis of control concepts for a vapour microturbine set with a generator with permanent magnets, intended to work in small heat and power plants. Control system variants differed by the selection of controlled signals and set parameters. Possible ways of control were discussed and compared with experimentally determined...
-
On the broadband behaviour of planar elliptical dipole-modal approach
PublikacjaBroadband behavior of planar elliptical dipole structure is analyzed using Illuminatin Modes (IM) approach. The current on patch has been expanded in series of eigenfunctions in form of Mathieu radial and angular functions. The frequency behavior of current distributions and related powers have been discussed to explain the mechanism of broadband operation of the dipole. Different behavior of radiations patterns in wide frequency...